I have both sitting in the shop. I am building a 72 chevy 4x4 with 14bolt rear 44 front. It is going to have a turbocharged 355 that should do about 800-850 engine horsepower. Its going to be a street/play truck probably 85% street 15% play.

If I do the th350 I'll have to buy the $275 direct drum. And then its a roll of the dice on what will break next. If I do the 400 I'll only have to buy the 34 element sprag for about $40. So for the trans easy choice.

But, the transfer cases is the 203 really that bad?? I have never heard any good about them. Does the chain break or what? I have never had any first hand experience with the 203.

I am not increadibly impressed with the 205 myself. We have broke several in Mom's mud truck.

Thanks

It all boils down to how much money you wanna spend really....

If I was you use the TH400/205 combo for strength and put a mid plate in your motor tranny combo keeping everything from twisting and you should be fine. If you could find a divorce 205 or 200 and run a 2WD 400 tranny and if you blow a tranny it is a quick swap out and rolling again. If you ran a divorce x-case you could get the shaft lengths the same and only need to carry 1 spare as well as not have to spend $$$ for high dollar front CV shafts.....

If I do the th350 I'll have to buy the $275 direct drum. And then its a roll of the dice on what will break next. If I do the 400 I'll only have to buy the 34 element sprag for about $40.
Thanks


Thats if you have the correct direct drum in your TH400.
Ive done a few and had to replace the drum with a high dollar TCI unit for use with the higher capacity sprag.

IMO if your spending the money on turbos etc etc
then spend the money wisely and use the only logical combo TH400 NP205

the chain on a 203 will stretch over time and will skip and buck, you do that with skinny down and youre going have a short race.

400 205, 465 205.

Thats if you have the correct direct drum in your TH400.
Ive done a few and had to replace the drum with a high dollar TCI unit for use with the higher capacity sprag.

IMO if your spending the money on turbos etc etc
then spend the money wisely and use the only logical combo TH400 NP205

1967 to 1972 caddy th400 will have the right drum.
six forward clutches in it, too.
edit:
among MANY other applications.

x2 on the 400/205. Running that much hp, you will need the 205. I would try to sell/trade the 350/205 combo for the right 205 to go behind your th400. Also, there might be some demand for that 203 that you have if someone needs it for a doubler apllication.

1967 to 1972 caddy th400 will have the right drum.
six forward clutches in it, too.
edit:
among MANY other applications.


True.
Thats the exact one Im running in my shortbed.
But theyre hard to find, which is why Ive used the TCI part.

I am not increadibly impressed with the 205 myself. We have broke several in Mom's mud truck.

Sig worthy there!

I'm starting a high HP build and will need to replace the TH350 with a 400. Grumpy or anyone, what other applications will have the large input drum?

Sig worthy there!

I'm starting a high HP build and will need to replace the TH350 with a 400. Grumpy or anyone, what other applications will have the large input drum?


IIRC CUCV and Diesel K30s should have the 6 disc drum.
I have personally found the 5 disc in most SBC and BBC TH400 205 combos.

I am not increadibly impressed with the 205 myself. We have broke several in Mom's mud truck.




I, for one, would like to know what the hell youre doing to an NP205 to break it?

Ive been running this case for a while, and have only managed to break one. You say you have broken several?
What are you breaking?

Well, in Mom's mud truck we have broken the front output shaft twice, the rear output shaft once. She also tore the splines out of the transfer side of the adapter.

Her truck is running a 700hp 421 sbc. The truck is a 70 blazer with 1/2 ton axles and 38" boggers. Its a mud race only truck, no playing. After putting yukon axles in the front of the 44 we have had no axle issues. The only trouble we have had out of the th350 was a broken stock style direct drum. I put a BTE drum with the 36 element sprag in, and its went 4 years with only freshen ups. I am afraid my truck is going to be a little too much for the th350.

In my 72 when it was my daily driver/tow vehicle, I stripped the tranny side of the adapter sleeve out of mine.

In my mud truck, I split the rear yolk at the splines. I also ripped the U joint U bolt holes off the side of the front yolk.

So, I am not sold on the 205.

In 2wd mode, how is a 203 coupled? Most of my playing will be in 2wd on the street anymore.

Thanks
Lynn

A TH400/205 with a 32spline front shaft will solve your problems.

If you keep breaking 205's time to see how fast the 203 will hold.

Well, in Mom's mud truck we have broken the front output shaft twice, the rear output shaft once. She also tore the splines out of the transfer side of the adapter.

Her truck is running a 700hp 421 sbc. The truck is a 70 blazer with 1/2 ton axles and 38" boggers. Its a mud race only truck, no playing. After putting yukon axles in the front of the 44 we have had no axle issues. The only trouble we have had out of the th350 was a broken stock style direct drum. I put a BTE drum with the 36 element sprag in, and its went 4 years with only freshen ups. I am afraid my truck is going to be a little too much for the th350.

In my 72 when it was my daily driver/tow vehicle, I stripped the tranny side of the adapter sleeve out of mine.

In my mud truck, I split the rear yolk at the splines. I also ripped the U joint U bolt holes off the side of the front yolk.

So, I am not sold on the 205.

In 2wd mode, how is a 203 coupled? Most of my playing will be in 2wd on the street anymore.

Thanks
Lynn

sounds like most of your problems are due to either a weak spot before or after the transfer case.... with three exceptions, two of which can easily be fixed.

Are you running a trans brake on this thing? sounds like you have had issues with loose u-bolts on the driveshaft, axle wrap on the rear end, poor mounting, worn stock parts, and the like. If you break the 30 spline front output, put a 32 spline output out of a dodge/ford np205 into it, that will fix that issue. If you are breaking rear outputs, check your driveshaft angle... Im willing to bet you didnt just shear it off.

if you can cushion the start, the truck might live a little longer... banging the transbrake is really hard on parts when you have slack in them, and the drive sleeves really suffer. maybe hook a linelock up to the brakes, set the transbrake with tension on the tire, and release both at the same time... that might relieve your broken part issue.

The stuff I broke on my mud truck were using a trans brake. Mom's truck is footbraked. My daily driver that broke the input sleeve was running a big bad 300 hp small block.

The driveline angles are not too bad, I've seen a lot worse. Moms truck is only lifted a couple inches and my mud truck only a couple too.

It's not an issue of, loose u-bolts on the driveshaft, axle wrap on the rear end, poor mounting, worn stock parts, I can assure you.

I just am not impressed with the 205.

Lynn

The stuff I broke on my mud truck were using a trans brake. Mom's truck is footbraked. My daily driver that broke the input sleeve was running a big bad 300 hp small block.

The driveline angles are not too bad, I've seen a lot worse. Moms truck is only lifted a couple inches and my mud truck only a couple too.

It's not an issue of, loose u-bolts on the driveshaft, axle wrap on the rear end, poor mounting, worn stock parts, I can assure you.

I just am not impressed with the 205.

Lynn
Well then you would be the only person on this site not impressed! They are pretty much Bullett proof! Of course what do I know? I only have a 582BB with 700ft lbs of tq on 44 boggers. The only thing I have broke was I twisted the front yoke off right after the splines. But I am pretty sure that it had worked loose, as I had had it back of before. But that can be expected when running a fair angle without a CV style shaft. O-Ya the yoke would be the same one as on a 203,205,208, etc etc.....

Go with the 400/205 and be done.:D

some people dont have a clue about what parts to use... i would have to suggest the tried and true NP208 for his needs... Should be right up his alley.

edit: questions for the original poster...

1. does the truck have traction bars?
2. is the application a rear slip yoke setup?
3. was there any bind or slop in the driveshaft yokes?
4. do you know how to load the drivetrain prior to launch?
5. are you aware that the stock drive sleeves are prone to breaking under load, especially the older 4 speed sm465 stuff? Wear will strip them out, sure as the sun rises.
F. if you think you can find a tougher gear driven transfer case for the same weight rating, i want to see it.

I have both sitting in the shop. I am building a 72 chevy 4x4 with 14bolt rear 44 front. It is going to have a turbocharged 355 that should do about 800-850 engine horsepower. Its going to be a street/play truck probably 85% street 15% play.

If I do the th350 I'll have to buy the $275 direct drum. And then its a roll of the dice on what will break next. If I do the 400 I'll only have to buy the 34 element sprag for about $40. So for the trans easy choice.

But, the transfer cases is the 203 really that bad?? I have never heard any good about them. Does the chain break or what? I have never had any first hand experience with the 203.

I am not increadibly impressed with the 205 myself. We have broke several in Mom's mud truck.

Thanks


If this is street only, just get a 203....leave it fulltime and be done with it...just remember to check and replace the chain when its worn out. All wheel drive, street truck with 8 hundo-million horsepower sounds fun. :flipoff2:

The 203's are great when you forget chain stretch and the extra 100 pounds that comes with them.

If you're really busting 205's like that you have other problems in the driveline, etc. the 32 spline ford output shaft is about the only upgrade they need to hold up to some serious abuse.

Answers for Grumpy,

1. All 3 trucks have ladder bars.
2. All 205's used were th350 married with fixed rear yolk.
3. Driveshafts were all in good condition with good spicer U joints.
4. Mom footbrakes the truck at 3000 rpm. My mud truck had a transbrake, I
always applied the brake at about 2500 to prevent it from rolling through the beams. I didn't hold the footbrake though.

5. Yeah, Ive seen a few broken 10 spline 4 speed sleeves before the only th350 sleeves I have heard of breaking were ours.

I've got a good 208 I'll just throw it in there along with some 12" blocks for the rear with no traction bars and a stock length driveshaft with wore out U-joints. It's bound to hold up as good as our 205's have.

Does your mom wear combat boots when she is mud racing?

That might be part of the problem...:tank:

I've got a good 208 I'll just throw it in there along with some 12" blocks for the rear with no traction bars and a stock length driveshaft with wore out U-joints. It's bound to hold up as good as our 205's have.



Dont forget the fuzzy dice:flipoff2:

I'm with GOF, you have something else going on. I easily run more HP than you and feed it through a 203 then the 205. My Rig weighs nearly 3 tons with me in it and I run 42" tires. I don't break 205s. I used to break transmissions, axle shafts, but no 205s. Since I built a manual shift 4l80, I don't have trans issues either anymore.

A 203 won't last the first time you throttle it on any surface with great traction.

until i see a photo of the traction bars, i will not be convinced that there is not major wheelhop going on. some designs lend themselves to it, others do not. if the traction bar is mounted at the bottom of the axle housing at a single point and runs to the frame at another single point, it is not a traction bar, it is a limiting link.

a properly designed traction bar will control axle wrap, will not limit suspension travel, and will allow sufficient articulation for any power level.

if you are using the stock strap style u-joint yokes on the axle or transfer case, you will have failures. if they are the u-bolt style, failures will be much less common. straps tend to stretch, where u-bolts dont stretch nearly as much.

If you have too short or too long a driveline, you will have failures. if you have a slip yoke that doesnt slip, you will have failures.

the 32 spline GM np205 input is designed to be a single coupling between the trans and transfer case, not a double coupling like the np205-th350 or 4spd, which allows for twice as much slop in the drivetrain, room for the engine to take up the slack with much abuse. not good for the th350, which only has a 27 spline shaft.

Again, photos, please. this will allow some of us to look at the weaker points in the drivetrain to evaluate for improvement.

of course, you may not want critical eyes looking at your shit. I dont blame you.

Get a TH400/NP205 with a 32 spline front driveline output. If you are worried about breaking the rear output, get a new Advanced Adapters HD shaft. For stronger yokes, use High Angle Drivelines billet flat flanges with 1410 drivelines. That is what I would run.

If ya want to get rid of the 205, I'll take it. :)

No GMtruxrule your Mom stole her combat boots, so she drives in flip flops now.:D

I am not looking to get rid of the 205's, I was just hoping I could make the 203 live because it was all I have that will work with the th400. It sounds like the 203 is a no go.

I'll start searching for a 400 205 or a divorced 205.

I don't have any pics of the traction bars. The traction bars on my s-10 are a single link with tabs welded to the bottom of the axle. On top, they hook up like a cal-trac bar with plates beside the spring bushing. On Moms blazer I welded 3/8" plates on the axle just like a drag race ladder bar setup. The bars are made of .120 1 5/8 tubing. They are bolted solid to the plates in the rear top and bottom. In the front I made the bolt hole in the bar slotted so it can work back and forth as the suspension geometry changes.

Thanks for the suggestions guys.
Lynn

If you find a divorced Dodge or International 205, it will have all 32 spline shafts, which is good.

No GMtruxrule your Mom stole her combat boots, so she drives in flip flops now.:D

I am not looking to get rid of the 205's, I was just hoping I could make the 203 live because it was all I have that will work with the th400. It sounds like the 203 is a no go.

I'll start searching for a 400 205 or a divorced 205.

I don't have any pics of the traction bars. The traction bars on my s-10 are a single link with tabs welded to the bottom of the axle. On top, they hook up like a cal-trac bar with plates beside the spring bushing. On Moms blazer I welded 3/8" plates on the axle just like a drag race ladder bar setup. The bars are made of .120 1 5/8 tubing. They are bolted solid to the plates in the rear top and bottom. In the front I made the bolt hole in the bar slotted so it can work back and forth as the suspension geometry changes.

Thanks for the suggestions guys.
Lynn

your traction bars are a limiting link. they do not allow the axle to articulate, they keep it from articulating. not good. even if the traction bar is mounted in line with the spring eye, it will limit travel and put the axle in a bind.

this is a traction bar designed properly:
http://i72.photobucket.com/albums/i183/jpfrk/DSC01414.jpg
it does not limit travel or articulation, only the amount of axle rotation. two are not needed, only one.