gearing down over mountain passes ?'s

[4Mogger]

Ok. Have you any experience with gearing down a load at max GVWR?
I am thinking about a situation like this:

My Tundra with 13500 pounds coming down Monarch pass (Colorado-between Gunnison and Salida on Hwy 50.) I don't want speeds over about 25-30 mph and it is STEEP.

The hill in my subdivison is steep too and I already know 2nd gear won't hold it!:eek:

So if 1st doesn't do what I want I am considering trying 4 low and picking a gear that works. This is only for about 5 miles or so on the descent.
Anyone ever go to 4 low to distribute some of the load holding/gearing down? Obviously, I wouldn't be doing this on snowpack or icy conditions (towing AT ALL that is :flipoff2: over a pass like Monarch) so I am referrring to dry conditions or rain maybe but I am not worried about traction.

Also keep in mind I am trying to stay out of the brakes completely. Brakes in this situation are for emergencies only IMO.

[ncl]

Not really on topic. But rather than taking Monarch Pass, look at swinging South at Poncha Spings and taking 114 through Poncha Pass and North Pass. (I think 114 was the route - don't have a map in front of me). The route makes a U swinging south of the pass and drops you out just east of Gunnison. (assuming you are heading west).

I made the tow this summer and went Monarch on the way. With my 2500 burb it was a tough haul up and smoking trailer brakes on the way down. A few people who were more experienced with the area suggested the route I posted above. While it is two passes (of almost the same altitude as Monarch) the pull/descent was MUCH easier. It is a few miles, but well worth it, especially pulling with a Tundra....

Nicholaus

[4Mogger]

Not really on topic. But rather than taking Monarch Pass, look at swinging South at Poncha Spings and taking 114 through Poncha Pass and North Pass. (I think 114 was the route - don't have a map in front of me). The route makes a U swinging south of the pass and drops you out just east of Gunnison. (assuming you are heading west).

I made the tow this summer and went Monarch on the way. With my 2500 burb it was a tough haul up and smoking trailer brakes on the way down. A few people who were more experienced with the area suggested the route I posted above. While it is two passes (of almost the same altitude as Monarch) the pull/descent was MUCH easier. It is a few miles, but well worth it, especially pulling with a Tundra....

Nicholaus

Like wheeling, I consider the tow a challenge too. May sound weird but I have driven every vehicle/motorcycle etc. that I have ever owned over Monarch in all kinds of weather (even down to one lane with 30 feet of snow wall on the sides) so it is more of the bar by which I evaluate a vehicle. So it is going over, I just want to have all the info I can to try to come up with a plan to do it safely.

Best time to date was in my '02 325i. It was the only time I ever wished I had the 330. The altitute really sapped the 2.5. but I literally flew over!

[joez]

Like wheeling, I consider the tow a challenge too. May sound weird but I have driven every vehicle/motorcycle etc. that I have ever owned over Monarch in all kinds of weather (even down to one lane with 30 feet of snow wall on the sides) so it is more of the bar by which I evaluate a vehicle. So it is going over, I just want to have all the info I can to try to come up with a plan to do it safely.


This isnt wheeling where when you overstep your vehicles capability you flop or break a couple parts. If you screw up towing you have other people on the road with you and are putting yours and everyone elses life in danger. Take the safer route, especially towing that much weight with a 1/2 ton Tundra.

[ncl]

I hit the top of Moarch, started the descent when a Mountain biker flew onto the road from the side. I locked up the tow rig and trailer tires :eek: :eek:

I was VERY happy to not take that route again on the way home.

Good luck on your journey over Monarch with that setup - not something I would ever consider doing. Had I tried, the biker would no longer be with us (I missed him by under two feet).

[4Mogger]

This isnt wheeling where when you overstep your vehicles capability you flop or break a couple parts. If you screw up towing you have other people on the road with you and are putting yours and everyone elses life in danger. Take the safer route, especially towing that much weight with a 1/2 ton Tundra.
Sorry. I know it can do it. I had 30,000 GVW behind a '99 Chevy (not a dually) with the diesel and took it slow with no problems--never touched the brakes.
The Tundra can hold back 6500 pounds, please.
I will keep it slow and the idea is..to NEVER TOUCH THE BRAKES, brakes are for emergencies as I have stated--like not hitting the biker. I have no doubt I could stop it with cool brakes.

[Eskimo]

What about First gear?

find your speed, and when you get 5-10 over it, stab the brakes to 5 under the speed, then let off completely. repeat as necessary.

[4Mogger]

What about First gear?

find your speed, and when you get 5-10 over it, stab the brakes to 5 under the speed, then let off completely. repeat as necessary.
That wouldn't work on this particular pass--you would overheat the brakes in no time.

[4Mogger]

I hit the top of Moarch, started the descent when a Mountain biker flew onto the road from the side. I locked up the tow rig and trailer tires :eek: :eek:

I was VERY happy to not take that route again on the way home.

Good luck on your journey over Monarch with that setup - not something I would ever consider doing. Had I tried, the biker would no longer be with us (I missed him by under two feet).
Sorry, calling BS on this one. I have MB'd and backcountry skied extensively in the area. No way is a biker going to accidentally run out onto the highway--he would have just gone down a 50 foot cliff on his way to a 1000 foot cliff. If this were true--should have saved the brakes for a real emergency--he had it coming

[The Jerk]

brakes are for stopping not emergencies. just use them every so often and be done with it.

[4Mogger]

Anyone ever go to 4 low to distribute some of the load holding/gearing down?
There was a question. I know there are *safer* alternatives. You'd think this was the Extreme Badmitton BB.

[4Mogger]

brakes are for stopping not emergencies. just use them every so often and be done with it.
I have followed rigs that have braked to slow for turns and by the time they are near the bottom, I can smell their brakes and the rotors are glowing!!
I generally pick a gear that I have to ADD throttle to just to maintain 30-45 mph and save the brakes.

[ncl]

Sorry, calling BS on this one. I have MB'd and backcountry skied extensively in the area. No way is a biker going to accidentally run out onto the highway--he would have just gone down a 50 foot cliff on his way to a 1000 foot cliff. If this were true--should have saved the brakes for a real emergency--he had it coming

I was just over the pass (gift shop/tourist area). He came from the high side of the Mountain, as he came near the road started to wobble and veared right into my path. I got flipped off by him to boot.

FWIW, I feel you are not concerned about safety (yours or others on the road). Good luck in your travels, but I'm glad I won't be near you.:shaking:

[4Mogger]

FWIW, I feel you are not concerned about safety (yours or others on the road). Good luck in your travels, but I'm glad I won't be near you.:shaking:
I will take some pics so you do not miss it completely.:flipoff2:
Seriously, the only people in danger will be those with high blood pressure that are forced to wait for the passing lanes behind me doing like 20mph-- and the crazed mountain biker that can't avoid a Tundra coming at him at....sigh...20 mph.

[Robert]

Yes, you can drop down into low range for better control and power during steep hills. However, with a heavy load, your t-case is going to get hot quickly. At the very least, I think I would change the oil afterwards. Depending upon how long the climb is going to take, you might want to pull over periodically and allow the t-case to cool off.
Take things very slow, you will be ok. I have pics of a friend pulling a 30K pound bulldozer over a steep pass near Crecent City with an old Power Wagon. Low range, 5mph the whole way:eek:

[sceep]

monarch is steep but its not toooo bad... at least its mostly straight up and down. LOL.

ever towed north into silverton on the 550. that is one windy, steep bitch

we rolled into silverton with 36k coming down the hill.

eskimo is right. throw it in first... brake now and then to lower your speed to 10-15 under your desired speed. if you find yourself still braking too often, lower your desired speed.

if you cant keep it going slow enough with this method YOU ARE OVERLOADED and need to either take an alternate route, or find a larger truck.

[4Mogger]

Yes, you can drop down into low range for better control and power during steep hills. However, with a heavy load, your t-case is going to get hot quickly. At the very least, I think I would change the oil afterwards. Depending upon how long the climb is going to take, you might want to pull over periodically and allow the t-case to cool off.
Take things very slow, you will be ok. I have pics of a friend pulling a 30K pound bulldozer over a steep pass near Crecent City with an old Power Wagon. Low range, 5mph the whole way:eek:
Mostly I am concerned about coming down. I do not expect any issues climbing. Thanks for the input!

[GRMhick]

Maybe its just me, but you shouldnt be towing 13,500 lbs behind a tundra.

[4Mogger]

Maybe its just me, but you shouldnt be towing 13,500 lbs behind a tundra.
That INCLUDES the Tundra. Only 6500 or so being dragged

[GRMhick]

oh oh oh, ok.

then Im not seeing the problem, of why you cant hit the brakes to slow down. How steep is the grade?

I'd still do 65 down 6-7% grades with my old half ton dodge, and trailer, about 11k between truck, truck, trailer, and gear.

[4x4not]

I dunno, I don't want to get into the 1/2 ton vs. real truck towing thing here, but if your truck can't handle going down the pass slow enough and you can't keep the brakes from overheating then maybe you need a bigger truck designed for that kinda load. An oil burner with exhaust brake will amaze you :flipoff2:

[4Mogger]

I don't know the grade but my GVWR is within Toyota's recommendations and I have 2 braking axles on the trailer

[4Mogger]

I dunno, I don't want to get into the 1/2 ton vs. real truck towing thing here, but if your truck can't handle going down the pass slow enough and you can't keep the brakes from overheating then maybe you need a bigger truck designed for that kinda load. An oil burner with exhaust brake will amaze you :flipoff2:
Yes but the other 350 something days a year this is a DDer.

[wes8517]

tundra 1st will max out at around 38-40, at least thats how it is on my 03 with v-8 and auto.

if you gotta go slower than just tap the brakes to keep it slower, no need to put it in 4 low if you ask me

wes

[4Mogger]

tundra 1st will max out at around 38-40, at least thats how it is on my 03 with v-8 and auto.

if you gotta go slower than just tap the brakes to keep it slower, no need to put it in 4 low if you ask me

wes

First should work fine then.

[4x4not]

Yes but the other 350 something days a year this is a DDer.
My oil burner is too :flipoff2:

[4Mogger]

tundra 1st will max out at around 38-40, at least thats how it is on my 03 with v-8 and auto.

if you gotta go slower than just tap the brakes to keep it slower, no need to put it in 4 low if you ask me

wes
the '05 has a 5 speed auto so 1st may top out a little quicker so that is a good thing.

[Kaiser5]

What about First gear?

find your speed, and when you get 5-10 over it, stab the brakes to 5 under the speed, then let off completely. repeat as necessary.
I went over Monarch both ways back in August towing my Jeep behind my 3/4 Suburban, 15k total weight. I use the method mentioned above because even in tow/haul mode the 4l80 won't hold me back on some of the steeper grades.
My biggest issue with that hill was not brakes but rising tranny temps.

[sceep]

10 miles of 6% grade.

no worse than flag to phoenix.

[GMCTruxrule]

I don't know the grade but my GVWR is within Toyota's recommendations and I have 2 braking axles on the trailer
There really is no "right" way or "wrong" way when it comes to descending steep grades with a load. Use a low gear, I don't know about 4 low, cause unless your tranny is in 4th gear, your engine is going to be turning some hellacious RPMs, your Tcase will get hot. When you crest the top of the hill and before you start down, slow way the hell down, and use your low gears AND brakes to keep your speed under control. Don't ride your brakes, but apply them hard and firm every once in a while to slow your speed and you will be fine. Worse comes to worse, just unless you have some serious switch backs on the hill that would make your truck and trailer roll of the road, just let the truck go (within reason of course).

[4Mogger]

There really is no "right" way or "wrong" way when it comes to descending steep grades with a load. Use a low gear, I don't know about 4 low, cause unless your tranny is in 4th gear, your engine is going to be turning some hellacious RPMs, your Tcase will get hot. When you crest the top of the hill and before you start down, slow way the hell down, and use your low gears AND brakes to keep your speed under control. Don't ride your brakes, but apply them hard and firm every once in a while to slow your speed and you will be fine. Worse comes to worse, just unless you have some serious switch backs on the hill that would make your truck and trailer roll of the road, just let the truck go (within reason of course).
I think there IS a wrong way. I have seen it plenty of times, generally evidenced by smoke (sometimes flames) filling the wheelwells of the rig and the driver attempting to control the rig at an unsafe speed. But the rest of the reply is on the mark.
I was just curious if anyone HAD used 4low to engine brake a load to safely descend a steep grade at max GVWR.
So far only one response that answered the question.

[MattS]

10 miles of 6% grade.

no worse than flag to phoenix.

Since 4mogger pointed out he has brakes on the trailer for emergency stops and the truck doesn't seem to be able to stop itself and the load with engine stopping power I just thought I would mention I was towing a mustang on the route that sceep mentioned. And my trailer brakes were not hooked up. (don't ask) :shaking: I stopped at a gas station somewhere along the route about 1/2 way down the hill. My 3/4 ton Dodge CTD with an Auto couldn't hold the load with engine braking and I smoked the hell out of my front pads and rotors. To the point there were plumes of white smoke. :eek:

[4Mogger]

To the point there were plumes of white smoke. :eek:
What's really cool is in low light or at night, they glow red!

[4Mogger]

Since 4mogger pointed out he has brakes on the trailer for emergency stops and the truck doesn't seem to be able to stop itself and the load with engine stopping power I just thought I would mention I was towing a mustang on the route that sceep mentioned. And my trailer brakes were not hooked up. (don't ask) :shaking: I stopped at a gas station somewhere along the route about 1/2 way down the hill. My 3/4 ton Dodge CTD with an Auto couldn't hold the load with engine braking and I smoked the hell out of my front pads and rotors. To the point there were plumes of white smoke. :eek:

What gear were you in and do you think if you had started out in a lower gear you could have held it?

[MattS]

What gear were you in and do you think if you had started out in a lower gear you could have held it?

I was going about 70 and was in OD when I crested the hill. I had it slowed down to 60, then 45 and kept going into a lower gear, but the grade overpowered the motor no matter what gear I had it in. Even when I stopped to let the brakes cool and started down again I HAD to use the brakes because the grade was enough to rev the motor to redline.

My old 2003 Dodge CTD had a 6 speed in it and coming out of Colorado it would do the same exact thing. I was hauling ALOT more weight. But it's been my experience that relying on the motor for stopping unless you have an engine brake is a bad idea.

The rotors took a beating but were fine. No hot spots, cracking or warping. I did replace the burnt pads and it stops fine now.

[demonranger]

he's going to have better compression braking w/ a gas motor than you will w/ a diesel because he has the built in restriction of the intake butterflies which diesel's dont' have, hence why you find exhaust brakes made for diesels and not for gas motors.

[Robert]

I was just curious if anyone HAD used 4low to engine brake a load to safely descend a steep grade at max GVWR.
So far only one response that answered the question.

No personal experience with 4low engine braking to decend a grade but,
with any engine the lower the gearing, the more powerfull the engine braking is. The gearing works both ways. Lower gears gives more pulling power when taking off. Lower gearing will also give better engine braking when coasting as well. Whatever braking horsepower your engine has is multiplied through the lower gearing. So dropping into 4low would give a lot more engine braking power.
I would be concerned however about using 4low with a heavy load in most vehicles. I just don't see the axles, driveshafts and t-case being up to handling the extra torque, higher loads, higher temperatures. On a paved road, you would have to keep the front hubs unlocked, so ALL of the torque would go through the rear axle. I can see a one ton doing this, but not a little 1/2 ton like Tundra.
All manuals for diesel engine brakes recomend dropping gears for better performance. The general rule of thumb is to decend a grade in the same gear required to climb that grade.
With diesels, you need an exhaust brake or compression brake to get engine braking. There is no restriction to airflow in diesels like there is in a gas engine. If just allowed to coast, they will continue to increase in RPM right into an engine overspeed situation.

[70~K5]

The general rule of thumb is to decend a grade in the same gear required to climb that grade.


This was true in the old days. But with new trucks and higher output engines you need to desend hills slower than you can climb them. Braking systems haven't caught up to HiPo engines in tow rigs.

[Black Sabbath]

Wow if diesels don’t get engine braking there must be something seriously wrong with my Duramax. Diesels actually get excellent engine breaking due to having high compression ratios. On the compression stroke the energy coming from the wheels is used to compress the air in the cylinder, remember the mechanical parts have to keep doing their thing even if their isn’t going to be fuel for the power stroke. Think air bump stops. By placing an exhaust restriction in you can raise the initial pressure of the cylinder which makes the engine work harder to raise the piston in its bore making the process even more effective. Notice how they make exhaust breaks (to keep the air in) rather than intake breaks? *Author’s Note: I may be completely talking out my ass here please correct me if I am wrong*

Back to the original question. I was actually doing this very thing Wednesday. The difference was that I was coming down a gravel road and wanted to keep it slooow. I was towing a Bobcat behind me down from a campground on a road that someone must have worked very hard to cut into the hill. Between the bumps, switch backs, and the cliff keeping the speed down seemed like a good idea, so I threw it in 4lo. It did a fine job for my purpose but I am not sure if it is something that I would want to try on the street or a long grade. Seems like a fine way to overheat/rev something. YMMV.

[dumass]

if you cant keep it going slow enough with this method YOU ARE OVERLOADED and need to either take an alternate route, or find a larger truck.

AMEN
:laughing: :laughing: :laughing:

[Brutpwr]

Anytime your towed weight exceeds your tow rig weight you can easily have problems with your brakes on the tow rig as they now have over twice the weight to deal with. In general most trailers do not have adaquate braking capacity when you have to use or rely on them to control speed on grades for long distances on 6 percent grades or steeper. Many trailers only have 10" drum brakes on one axle and these will fade and overheat with two hard applications with a 7000 pound trailer load from highway speed back to back. Even with both axles with brakes they will fade almost immediately. The 12 inch brakes on the heavier duty trailer axles are a bare minimum for use on a heavy trailer as they are much more powerful and have much more capacity to carry heat away from the brake shoes and more area to dissapate the heat to the surrounding air. Even most older midsized cars had 11" rear brakes as did most older 1/2 ton trucks. You would not want 10" drums on your one ton tow rig would you??? Using low range is very useful for both climbing and descending steeper grades with a heavy towed load. When climbing even with the bigger turbo diesels sometimes the lower gear is too low (near redline) and the next gear up is too high and either the turbo does not spool up and make power or it loads too much and exhaust temps creep up dangerously high. When you shift to low range the gaps between gears almost disappear. Kind of like a poor mans gear splitter. Gennerally if your speed in first gear is greater than 25 MPH at 4000 RPM then you will benefit from shifting into low range when descending long steep grades of 6 percent or more. I have had to use low range on grades of 11 percent and even then I had to use the brakes with second gear as first gear would hold the load/speed but was a bit to slow so I would let the load roll out to 20 MPH and brake lightly to 15 and repeat. While the brakes did not overheat I could tell the trailer brakes were getting warm as I had to increase truck braking towards the bottom of the grade. By going slower you gain time to allow the brakes to cool which is what is needed on a long grade. Anytime you are unsure of the capacity of the truck and trailer to stop safely at the bottom of a long grade you should approach the top of the grade at around 15 MPH for a 10 percent grade or about 30 for a 5 percent grade and on most rigs you will find a comfortable speed to descend in the first 1/2 mile or so where you won't have to rely on the brakes too much. Remember that if you double the speed it will put 4 times the heat into your braking system and this is why faster speeds cause brake fade/smoke.

Jason :)

[98hd]

Wow if diesels don’t get engine braking there must be something seriously wrong with my Duramax. Diesels actually get excellent engine breaking due to having high compression ratios. On the compression stroke the energy coming from the wheels is used to compress the air in the cylinder, remember the mechanical parts have to keep doing their thing even if their isn’t going to be fuel for the power stroke. Think air bump stops. By placing an exhaust restriction in you can raise the initial pressure of the cylinder which makes the engine work harder to raise the piston in its bore making the process even more effective. Notice how they make exhaust breaks (to keep the air in) rather than intake breaks? *Author’s Note: I may be completely talking out my ass here please correct me if I am wrong*

Back to the original question. I was actually doing this very thing Wednesday. The difference was that I was coming down a gravel road and wanted to keep it slooow. I was towing a Bobcat behind me down from a campground on a road that someone must have worked very hard to cut into the hill. Between the bumps, switch backs, and the cliff keeping the speed down seemed like a good idea, so I threw it in 4lo. It did a fine job for my purpose but I am not sure if it is something that I would want to try on the street or a long grade. Seems like a fine way to overheat/rev something. YMMV.


You must realize that the throttle plates closing on a gas motor creates a vacuum, which makes the compression braking more efficient on a gas motor than on a diesel, as there is nothing to create a vacuum.

I believe that an engine brake (jake brake) actually works on this concept, by keeping the exhaust valve closed on the down stroke to create a vacuum.

That being said an exhaust brake on a diesel is awesome in the hills. With my first diesel and first exh. brake I went down a 3-4% grade (I know not that steep) w/ approx. 6500lb load. The truck kept accelerating w/ the e-brake off, when I turned it on it was a huge difference and it actually slowed the truck down more than I wanted. I ended up turning it on and off to keep a speed I wanted.

[4Mogger]

Anytime your towed weight exceeds your tow rig weight you can easily have problems with your brakes on the tow rig as they now have over twice the weight to deal with. In general most trailers do not have adaquate braking capacity when you have to use or rely on them to control speed on grades for long distances on 6 percent grades or steeper. Many trailers only have 10" drum brakes on one axle and these will fade and overheat with two hard applications with a 7000 pound trailer load from highway speed back to back. Even with both axles with brakes they will fade almost immediately. The 12 inch brakes on the heavier duty trailer axles are a bare minimum for use on a heavy trailer as they are much more powerful and have much more capacity to carry heat away from the brake shoes and more area to dissapate the heat to the surrounding air. Even most older midsized cars had 11" rear brakes as did most older 1/2 ton trucks. You would not want 10" drums on your one ton tow rig would you??? Using low range is very useful for both climbing and descending steeper grades with a heavy towed load. When climbing even with the bigger turbo diesels sometimes the lower gear is too low (near redline) and the next gear up is too high and either the turbo does not spool up and make power or it loads too much and exhaust temps creep up dangerously high. When you shift to low range the gaps between gears almost disappear. Kind of like a poor mans gear splitter. Gennerally if your speed in first gear is greater than 25 MPH at 4000 RPM then you will benefit from shifting into low range when descending long steep grades of 6 percent or more. I have had to use low range on grades of 11 percent and even then I had to use the brakes with second gear as first gear would hold the load/speed but was a bit to slow so I would let the load roll out to 20 MPH and brake lightly to 15 and repeat. While the brakes did not overheat I could tell the trailer brakes were getting warm as I had to increase truck braking towards the bottom of the grade. By going slower you gain time to allow the brakes to cool which is what is needed on a long grade. Anytime you are unsure of the capacity of the truck and trailer to stop safely at the bottom of a long grade you should approach the top of the grade at around 15 MPH for a 10 percent grade or about 30 for a 5 percent grade and on most rigs you will find a comfortable speed to descend in the first 1/2 mile or so where you won't have to rely on the brakes too much. Remember that if you double the speed it will put 4 times the heat into your braking system and this is why faster speeds cause brake fade/smoke.

Jason :)

Thanks for the info!

[Robert]

I believe that an engine brake (jake brake) actually works on this concept, by keeping the exhaust valve closed on the down stroke to create a vacuum.

That being said an exhaust brake on a diesel is awesome in the hills. With my first diesel and first exh. brake I went down a 3-4% grade (I know not that steep) w/ approx. 6500lb load. The truck kept accelerating w/ the e-brake off, when I turned it on it was a huge difference and it actually slowed the truck down more than I wanted. I ended up turning it on and off to keep a speed I wanted.


You are a little off on your concept of an engine brake. What most people call "Jake Brakes" are compression brakes. They use the compression build up in the cylinder to slow the engine down. As the piston is coming up on TDC compression, the exhaust valves are cracked open to bleed off the compression and prevent ignition of the fuel. Then the piston cycles down on the power stroke with out any forces on the crankshaft.
Without a compression brake, the piston would still be pushed downward by the compression pressures, minimizing engine braking.

[4Mogger]

I finally did this the other day...brought almost 14K# gvw down Monarch pass with my Tundra. I used low range and went as slow and as fast as I wanted and never even so much as touched the brakes.
Makes a great argument for a 4x4 tow vehicle if you live or tow in the mountains.
I was all worried about this for no good reason. I had plenty of engine braking power left and could easily slow for turns and such. A little prudence and skill can do the job of a much bigger rig with less truck than I thought. This lightweight truck continues to impress me. It is more of a hammer than a sledge but if you know that and can compensate it is manageable.

[Flexy Flatty]

what gear was the tranny in and how fast were you going?

[pilothillcrawler]

OK... I would think that if you need to go down a grad in 4 f-ing low than you are towing to much for that truck on that hill.
Strait out of the California Class A hand book, decend hills in one to two gears lower than it requires to climb (I know most 1/2 ton trucks don't have enough gears to go two gears lower, but you can do one gear lower.) Then when you find your safe speed, let it creep up about 5-10 MPH higher and use your brakes to bring it back about 5 MPH lower than you desired MPH. I tow ALOT more weight than you over and around the Sierras out hear in California and this principle works perfect at 50-70 MPH around here I think it will work in you condition. The principle also works in the steep ass canyon roads when going down 8-10% switch backs at anywhere from 5-15 MPH. (Oh yeah, you are suppose to use you breaks to maintain the proper speed, that is why they are called SERVICE beakes.)

Finally on the note of the "Jake Break/Exhaust break", two completly different things. A Jake Break are the noisy ones on big rigs. They keep the INTAKE valve closed on the intake stroke and then open back up at the bottom, that is where you get all the noise from the valve opening and all the air rushing in. An Exhaust break is just what is sounds like. It restricts the Exhaust leaving the cylinder on the exhaust stroke.

OK I think I covered everything. Oh yeah, from the sounds of it, if you are stating that you are within load limits of the Tundra (and it sounds like you are) then my breaking principle stated above should work perfect, with VERY little to no break fade, especially if you have beakes on both trailer axels.

[70~K5]

If you have full time 4x4 disregard this. If you have part time 4x4 you'll create a bind in your transfer case and sooner or later you'll break something using it on clear dry pavement.

[SanDiegoCJ]

I will take some pics so you do not miss it completely.:flipoff2:
Seriously, the only people in danger will be those with high blood pressure that are forced to wait for the passing lanes behind me doing like 20mph-- and the crazed mountain biker that can't avoid a Tundra coming at him at....sigh...20 mph.

IMO, with your attitude you should park the vehicle and walk. Thankfully
you're in Colorado and no where near me. I don't want to be anywhere near
you while driving on the highway.

[BikerSC]

IMO, with your attitude you should park the vehicle and walk. Thankfully
you're in Colorado and no where near me. I don't want to be anywhere near
you while driving on the highway.

x2

That whole thread had no point as he already had his mind made up, and wasn't planning on listening to anyone's advise.

[4Mogger]

x2

That whole thread had no point as he already had his mind made up, and wasn't planning on listening to anyone's advise.

I asked if anyone had ever gone to 4low to bring a big load down a steep pass...I was not asking for opinions from people who think doing so is stupid or theoretically dangerous. I can tell you that it was a completely safe thing to do. 1000 times safer than trying to do the same thing in 2hi KNOWING full well (from personal experience driving and towing in the mountains) that I would smoke the brakes and quite possibly lose control of my speed.

[4Mogger]

what gear was the tranny in and how fast were you going?

1st gear to start off until I found that 2nd would hold the speed I wanted to maintain and even then I was on the gas a bit to maintain 15 to 25 mph depending upon the grade and turns.

[4Mogger]

OK... I would think that if you need to go down a grad in 4 f-ing low than you are towing to much for that truck on that hill.
Strait out of the California Class A hand book, decend hills in one to two gears lower than it requires to climb (I know most 1/2 ton trucks don't have enough gears to go two gears lower, but you can do one gear lower.) Then when you find your safe speed, let it creep up about 5-10 MPH higher and use your brakes to bring it back about 5 MPH lower than you desired MPH. I tow ALOT more weight than you over and around the Sierras out hear in California and this principle works perfect at 50-70 MPH around here I think it will work in you condition. The principle also works in the steep ass canyon roads when going down 8-10% switch backs at anywhere from 5-15 MPH. (Oh yeah, you are suppose to use you breaks to maintain the proper speed, that is why they are called SERVICE beakes.)

Finally on the note of the "Jake Break/Exhaust break", two completly different things. A Jake Break are the noisy ones on big rigs. They keep the INTAKE valve closed on the intake stroke and then open back up at the bottom, that is where you get all the noise from the valve opening and all the air rushing in. An Exhaust break is just what is sounds like. It restricts the Exhaust leaving the cylinder on the exhaust stroke.

OK I think I covered everything. Oh yeah, from the sounds of it, if you are stating that you are within load limits of the Tundra (and it sounds like you are) then my breaking principle stated above should work perfect, with VERY little to no break fade, especially if you have beakes on both trailer axels.

If you had any experience towing in the mountains at much steeper grades you would know that using "service brakes" to control speed is completely out of the question. The grade is too steep and far too long to expect even the best modern braking system to hold out. I see those who try all the time, they are easy to spot because they are either buried in the runaway truck ramp or clearly driving faster than I am sure they would prefer with smoke coming from every brake on the rig.

[Big91RustyBucket]

IMO, with your attitude you should park the vehicle and walk. Thankfully
you're in Colorado and no where near me. I don't want to be anywhere near
you while driving on the highway.

x2

That whole thread had no point as he already had his mind made up, and wasn't planning on listening to anyone's advise.

I agree with both of you. I used to tow with a 01 GMC Sierra the truck hated the truck and trailer behind it. IT is worth getting a bigger truck for your safety and others. You mr 4mogger are a jackass , and I am glad you are not anywhere near me. Your 4 runner looks sweet but I am surprised with your attitude and the build of that you don't have a diesel .

[4Mogger]

I agree with both of you. I used to tow with a 01 GMC Sierra the truck hated the truck and trailer behind it. IT is worth getting a bigger truck for your safety and others. You mr 4mogger are a jackass , and I am glad you are not anywhere near me. Your 4 runner looks sweet but I am surprised with your attitude and the build of that you don't have a diesel .
If I needed a diesel, I would go get one. So far, I have not needed one.

[Joey D]

How will you avoid binding up the t case? This would work fine if you had a 203 full time case but I wouldn't drive on the road with it in 4 lo.

[Hendo]

I finally did this the other day...brought almost 14K# gvw down Monarch pass with my Tundra. I used low range and went as slow and as fast as I wanted and never even so much as touched the brakes.
Makes a great argument for a 4x4 tow vehicle if you live or tow in the mountains.
I was all worried about this for no good reason. I had plenty of engine braking power left and could easily slow for turns and such. A little prudence and skill can do the job of a much bigger rig with less truck than I thought. This lightweight truck continues to impress me. It is more of a hammer than a sledge but if you know that and can compensate it is manageable.

x3 on that too,anything could happen with that load ,ujoint,etc

[4Mogger]

How will you avoid binding up the t case? This would work fine if you had a 203 full time case but I wouldn't drive on the road with it in 4 lo.

I do not believe there was any significant bind since I made no sharp turns. Not only that, but I was never under power, only using the engine to brake, a condition that is not prone to produce significant bind IMO.

Today I tried to use engine braking alone to descend a very steep mountain pass in my work truck-- '05 Dodge 2500 with the Hemi (in 2wd 1st gear). It was graded gravel and in first gear the truck quickly jumped up to 30 mph and I had to brake. This was with zero load in the bed and nothing in tow.

Bottom line is that if the grade is severe enough and long enough, you have no other choice but to use the transfer case to increase gearing advantage to allow the motor to hold the grade.

[the_experience3006]

I will be the FIRST to admit I have no experience towing down long grades. I have towed down long grades...and down steep grades...but never both at the same time.

The closest I've gotten is about 5 miles of 6% grade in my bus. Now I know this isn't additional weight to the vehicle. In fact, I'm 10,000 lbs below GVWR, but rest assured I was nervous as I crested that hill. I have essentially no engine braking because I don't have a lockup converter, retarder, exhaust brake...none of that good stuff. I can downshift, but it's only so effective. So basically I'm left with the air service brakes. They are properly adjusted for slack, but I have NO problems with fade, compressor recovery times, any of that. I put that Allison in 3rd gear and as posted previously I use the stab style of safe-speed braking, just as the CDL manual instructs you.

I guess my question is...is going down a 10 mile 6% grade at say 75% of your tow rating with adjusted and working trailer brakes and a geared down rig REALLY that bad? It just seems to me that careful, well planned use of the service brakes along with never exceeding your safe speed wouldn't be that difficult, but like I said...I'm the first to admit that I have never done such a thing.

[6.2Blazer]

On almost all stock trucks, there should be absolutely no issues with driving in a 4-lock position on paved roads in regards to durability. The tires should always have less traction, meaning they will hop or skip, or whatever, way before you ever get to the breaking point of some 4wd component. Just think about it, otherwise anytime you ran a trail and got in a situation where you spinning on rocks you instantly grenade something as most 4-wheeling situations put a lot more stress on components than running on a paved road.

I also do automotive durability testing for a living, and we regularly run OEM trucks and SUVs in a both 4-high and 4-low for long periods of times on paved surfaces including lock to lock turns, speeds well in excess of public road speed limits, and usually for at least 10,000 miles if not 20-30K, and I rarely ever see a drivetrain failure that could be definitely contributed to running in 4wd on paved surfaces...in fact the frequency of these failures was much less than failures that had absolutely nothing to do with 4wd. I have also performed temperature studies in regards to operating a truck in 4wd while ascending grades in multiple repetitions and the t-case basically reached a certain temperature and stabilized there, well within the operating limits of it. The auto trans did however continue to increase temperature (no auxiliary cooler or anything).

So overall, I see absolutely no reason why you could not use 4-low while descending a hill. Especially if you only need to maintain 25-30 mph

[rockota]

I tow my 4Runner w/ an 04 DC... It does just fine, and frankly, better (mileage, comfort, stability) than the 04 Cummins I had for 10 short days. Having said that, I think this is a situation where a big-brake kit is something that should be seriously considered. Throwing larger disks on the front and disks in the back will allow you to bring the 05 into the 07 braking cability range.

Not sure I'd drive down a grade like that - I'm a pussy - so I'm glad I don't currently live in CO. :)

[ddestruel]

IMO, with your attitude you should park the vehicle and walk. Thankfully
you're in Colorado and no where near me. I don't want to be anywhere near
you while driving on the highway.

IMHO there is more than one way to get a truck and trailer over the mountain safely and compression gearing with a t-case is not as uncommon as you all may think


Nothing wrong with using lower gears of the t-case to compression down a hill. seen many people do that. similar to the concept that log truck employ with a browny box ect on older trucks. seen it used for years as a dependable way for RV owners to bring thier giant rv's out of the hills as well alot of livestock haulers i know do it on numerous grades in idaho like white bird especially with thier older 1980's and 70's tow rigs 3/4 ton chevys and fords that quite frankly are probably equally equipt to the new tundra considering how small the rotors and pads were back in those model years and most of them are towing into the 15k-20k lbs loads and just the motor alone isnt enough in hi range to effectively slow the truck without smoking the brakes so they employ the t-case low range and a little more tact.



Diesel is not necessary in this case in fact diesels havent even come into main stream usage until the last 10 years. honestly a gas engine is plenty safe and a 1/2 ton is plenty of truck to haul 8000lbs. its the automatic is the biggest risk in the equation. 14k lbs is not a lot of wieght with a tundra that probably wieghs in at 5400-6000 lbs so he is towing a 7000-8000 lbs trailer if i recall he had brakes on the trailer and the truck and if remember my chofures license test for TT umpteen years ago they told us "use the gears to keep the truck slow avoid using your brakes until you have to" and that was DOT telling us that. i would like to think the same rules would apply in lighter vehicles



if he was talking a 10k trailer maybe youd all have an argument i always find these debates humerous. i think there are many different advise givers on the web those who think they know what they are doing, those who have an opinion and who maybe do it on the weekend and those who do it and make money day in and out.

[needmorepower]

You assholes are unbelievable, this guy is only trying to tow his shit safely. He is well within the limits of his vehicle and manufacturers specs. And you all have to jump on the "if it ain't diesel, it ain't safe" bandwagon. If you have never been on the road, then you don't know what the fuck you are talking about. On long grades, even with engine brakes (jake brake) big rigs still have to use their brakes on long grades.

I would like to see even one of you asshats go tell an OTR trucker that he needs a bigger truck! I would even pay to see how he or she for that matter, makes it so you can talk through your belly button.

[4Mogger]

I tow my 4Runner w/ an 04 DC... It does just fine, and frankly, better (mileage, comfort, stability) than the 04 Cummins I had for 10 short days. Having said that, I think this is a situation where a big-brake kit is something that should be seriously considered. Throwing larger disks on the front and disks in the back will allow you to bring the 05 into the 07 braking cability range.

Not sure I'd drive down a grade like that - I'm a pussy - so I'm glad I don't currently live in CO. :)

Did I mention that I did not even touch the brakes? Now I am just being a prick. But seriously, I am not putting a dime into upgrades on this Tundra. It is a daily driver and I put gas in it and change the oil and that is it.

[rock-rod]

Out of curiosity, how does your tundra do going to the passes towing a load?

[Urban Wheeler]

I believe that an engine brake (jake brake) actually works on this concept, by keeping the exhaust valve closed on the down stroke to create a vacuum.


Jake brakes on semis are completely different from what you put on your pickup. There are some solenoids to direct oil flow. When they are on, the exhaust valve is hydraulically connected to the injector cam. What happens is the exhaust valve opens at TDC, releasing all the energy used to compress the air.

Pickup truck brakes work by holding the exhaust in. I wonder how much pressure they build up?

[Urban Wheeler]

If you had any experience towing in the mountains at much steeper grades you would know that using "service brakes" to control speed is completely out of the question. The grade is too steep and far too long to expect even the best modern braking system to hold out. I see those who try all the time, they are easy to spot because they are either buried in the runaway truck ramp or clearly driving faster than I am sure they would prefer with smoke coming from every brake on the rig.

And those people are just dumb. You do not apply the brakes the whole way down. Downshift and let the engine do the work. I have hauled heavy stuff in mountain passes, always used the jakes, and sometimes used the SERVICE brakes to scrub some speed. Rarely does compression alone hold the truck at a comfortable speed. I always take it 10 to 15 mph slower than what I need to.

And I don't use the brakes lightly, I usually get on it hard enough to scrub 20 mph in about 3 seconds.

[70~K5]

Jake brakes on semis are completely different from what you put on your pickup. There are some solenoids to direct oil flow. When they are on, the exhaust valve is hydraulically connected to the injector cam. What happens is the exhaust valve opens at TDC, releasing all the energy used to compress the air.

Pickup truck brakes work by holding the exhaust in. I wonder how much pressure they build up?


I've driven a rig with a blue ox exhaust brake on a small cam cummins and it wasn't anything like a real jake brake, couldn't tell much difference on or off.

[4Mogger]

Out of curiosity, how does your tundra do going to the passes towing a load?

It does great! This motor, like every other Toyota, loves to rev. I just keep OD turned off and let it rev. I easily holds the speed limit even going up the pass.

[rocknbronco]

Wouldnt using four low in the pavement eat the tires up and kill the tranny and t case in one shot?????

[pilothillcrawler]

If you had any experience towing in the mountains at much steeper grades you would know that using "service brakes" to control speed is completely out of the question. The grade is too steep and far too long to expect even the best modern braking system to hold out. I see those who try all the time, they are easy to spot because they are either buried in the runaway truck ramp or clearly driving faster than I am sure they would prefer with smoke coming from every brake on the rig.

I quit, you are an ass. you didnt read the whole thing. I said use one to two gears lower going down the hill than you did to go up the hill, this creates compression. :shaking: then you use the service breaks periodically, to bring the speed back down about 5-15. You scrub some speed off with service breaks as stated by others on here also. those people that you mention are stupid and were relying completly on breaks to maintain speed.
but what the hell your ignorance is pretty intertaining.:lmao::shaking:

[4Mogger]

Wouldnt using four low in the pavement eat the tires up and kill the tranny and t case in one shot?????

Apparently not. My tires are perfect. And the tcase and tranny are functioning normally. Wierd. It is almost like the exercise had absolutely no adverse affect on the truck whatsoever. Hmmmm.

[ky scrambled]

I will be the FIRST to admit I have no experience towing down long grades. I have towed down long grades...and down steep grades...but never both at the same time.

The closest I've gotten is about 5 miles of 6% grade in my bus. Now I know this isn't additional weight to the vehicle. In fact, I'm 10,000 lbs below GVWR, but rest assured I was nervous as I crested that hill. I have essentially no engine braking because I don't have a lockup converter, retarder, exhaust brake...none of that good stuff. I can downshift, but it's only so effective. So basically I'm left with the air service brakes. They are properly adjusted for slack, but I have NO problems with fade, compressor recovery times, any of that. I put that Allison in 3rd gear and as posted previously I use the stab style of safe-speed braking, just as the CDL manual instructs you.

I guess my question is...is going down a 10 mile 6% grade at say 75% of your tow rating with adjusted and working trailer brakes and a geared down rig REALLY that bad? It just seems to me that careful, well planned use of the service brakes along with never exceeding your safe speed wouldn't be that difficult, but like I said...I'm the first to admit that I have never done such a thing.


what is the grade on 35 coming/going from Duluth?

[4Mogger]

I quit, you are an ass. you didnt read the whole thing. I said use one to two gears lower going down the hill than you did to go up the hill, this creates compression. :shaking: then you use the service breaks periodically, to bring the speed back down about 5-15. You scrub some speed off with service breaks as stated by others on here also. those people that you mention are stupid and were relying completly on breaks to maintain speed.
but what the hell your ignorance is pretty intertaining.:lmao::shaking:

I'll bite. You are clearly devoid of any significant towing experience. If I had wanted your theory I would have asked for theories to be offered.

I already stated. 1st gear (not "one or two gears lower" you freaking dolt) but the lowest gear available to me would not hold the load for two seconds before accellerating out of control on this grade. When maximum safe speed is less than 20 miles per hour and this is reached in less than a few seconds in the lowest gear available (without the use of the transfer case reduction) then it is safe to say that the service brakes (similar to your breaks) may not last the 10 to 12 miles down the mountain.

My "ignorance is pretty intertaining?"

Your ignorance is not entertaining in the least. But watching you actually bring a load down Monarch pass...THAT would be entertaining.

[ramv]

Apparently not. My tires are perfect. And the tcase and tranny are functioning normally. Wierd. It is almost like the exercise had absolutely no adverse affect on the truck whatsoever. Hmmmm.

We used to do this with a '98 Chevy CC DRW work truck towing 20k+ on some steep hills. Oddly enough, the truck didn't blow up in the 50 000 miles I worked there, but it went through tires and brakes quick from always being overloaded. I am still amazed that the t-case (BW in the crew cabs) stayed together with close to 30 000 lb screaming down passes and the 454 tach-ed out.

Not something I would do with my own truck, but it sure would be nice to have a 2lo option on newer rigs. (My buddy's F-350 has it, since the auto hubs never work)

[rock-rod]

I haul my junk up and down the passes frequently, including Monarch and Wolfcreek. 2nd gear and cycling the brakes works just fine to keep speeds safe and controlled. Never had a problem with brakes smoking or fading out.

tow rig is a '98 2500 burb and the trailer with the jeep weighs about 7500 lbs. My trailer also has brakes on both axles, but that's a recent change. I used to only have brakes on one axle.