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Non-diluted tech...auxiliary gearing

2K views 20 replies 12 participants last post by  Mr.Kleen 
#1 ·
Okay, I sense some tech-o-philes getting restless, so here's a theory I'd like to bounce off a few of you.

I see an opportunity for adapter manufacturers to step away from the useless drive train lengthening adapters currently available, and move towards the direction of adapters with added function, like lower gearing and such.

Here's my idea, it's similar to the Klune underdrive and the Ranger OD/UD, a trans to t-case adapter that is shift-able from a 1:1 range for normal use, to maybe a 2:1 low, and a 0.75:1 high, mainly for use with the short truck four speeds, like the SM465, SM420, and NP435. Simple enough, but what if you were to also drop the output of the trans at the same time? Like maybe to the same level as the transmission's idler shaft. You would need the input shaft to turn a reverse idler, with the ratio choices on it of course, that would turn the output shaft. Think of a truck four speed in reverse, the bottom idler is now turning forward.

The shifting mechanism and reverse idler could sit off to the side, opposite the front output of the t-case, and in the case of the truck four speeds, you could end up with a transfer case clocked flat, and flush with the bottom of the big four speed, creating excellent drive shaft angles and a smooth belly, if the drive train was raised enough.

Okay, shoot some holes in my theory, or tell me what would be needed to do it. Is my tech totally weak, or is this something that could be done?
 
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#2 ·
I have some left over planetary gear sets left over form NP231 terra low conversions. I've been thinking that some day I might take a look and see if I could make something out of them :D

Then I started thinking about whayt I would have to do for a shifting mechanism and put the thoughts on the back burner

Now that I have a free grand waggy that might needs some more crawl...

How well would the stock NP231 gears hold up to a 360 with an Auto tranny in front of them and an NP208 behind them?

I think I could make a short adapter that I can fit the planetaries in figure out how to shift them and then have a 4.something crawler gear comboe dealio.
 
#3 ·
Here's a hole:

Whatever is last in your drivetrain (presumably the Ranger OD/UD since that would traditionally be on the output shaft) would be subject to horrendous torque loads. Not to mention your Transfer case had better be an Atlas or an NP205...
 
#4 ·
NP208 is a heavy duty tcase.

HMMM I night be onto something here

NP208 with a few crawler boxes in front of it made from the planetary gearsets from a NP231 or another 208

XJ's would be able to have a multi transfercase dealio like the Toyota can do.
 
#5 ·
I love these kinds of ideas, but I see a few holes.

First, if the adapter is built into the gear box, your looking a unique housing for every different type of combination, significantly increasing the cost to produce. You could have the gear box with a generic bolt pattern on both ends and different (but very short) adapters to allow you to connect it two the different tranny's and t-cases, but like you said that already exists in a klune, or ranger unit. I'm not sure how much a klune costs, but I know it's up there, and it uses a existing already proven design (based on NV low range sections). What you are talking about is a totally new gear box, I imagine the cost would be through the roof just to develop and test it.

One idea a had a while ago was developing a new back 1/2 to a NV231 t-case. If you done or seen a SYE you know how you basically take off the whole back of the case, imagine if you could replace that back half with something resembling a standard gear drive t-case, you would still keep the front half with it's planetary reduction, but would gain a second low range in the back, while keeping the majority of the housing, and replacing just the back of the case. Of course there are a variety of problems with this such as shift linkages, adequate room for all the new gears, costs, and weakness of the 231 aluminium case.

I have also had a portal axle idea floating around in my head for the better part of six months. It would basically bolt right to a standard axle, and would not require flipping the axle like mog outters. The downside? Would cost a fortune to design/develop/test, would only allow for a few inches of offset (which might not be bad judging from some of the posts I've read on mogs), and would result in at least 3:1 at the hub, probably more like 4:1, so you'd have to run 54" tires, or run your transmission backwards to have anything useable on the road. Not to mention that most stock axle knuckles would probably not handle the additional loads placed on them by a portal hub.

Fun to dream though. Anyone else have any crazy ideas?

Chad
 
#6 ·
chadl said:
First, if the adapter is built into the gear box, your looking a unique housing for every different type of combination, significantly increasing the cost to produce. You could have the gear box with a generic bolt pattern on both ends and different (but very short) adapters to allow you to connect it two the different tranny's and t-cases, but like you said that already exists in a klune, or ranger unit. I'm not sure how much a klune costs, but I know it's up there, and it uses a existing already proven design (based on NV low range sections). What you are talking about is a totally new gear box, I imagine the cost would be through the roof just to develop and test it.

That was the first thing through my head. Why? when the applications are different with each bolt pattern? As you sadi the Klune is already out there. I like the idea, but I cant really see it being very cost effective to produce. However, you build one...I will test it for ya :flipoff2: T18 on the front and Atlas in the back ;)

Good idea :flipoff2:
 
#8 ·
And when you relocate the output, you loose the ability to have it free-wheel, for lack of a better term. You're always going to be spinning gears, so you might as well do a .75:1 high 2:1 low and just throw the 1:1 idea right out the window
 
#9 ·
Threre is already an adapter from AA for Land Cruisers that offers a two speed auxillary, so this is not a new idea, but it needs to be expanded out.

There is also the Bradnob Mountain Gear auxillary box. It literally uses the auxillary section gears from an Eaton 13 Speed truck transmission. The case is(was? Not sure if they are still around) made of thick welded sheet metal. The shifter mechanisms uses the air shift valves off of the original Eaton. You would get an underdrive, direct, and overdrive.
I thought the Bradnob was an excellent idea. Pre-existing gears, that will never break, simple case. But they were very expensive.
 
#10 · (Edited)
edit: Sorry, got tied up with this damn job halfway through typing my response.

The NP231 Planetary reduction box thing has been done before, and it's basically the same concept as the Klune V. That's a simple one, well, kinda.

Jakester, the Ranger OD or UD auxilliary transmission is installed between the transmission and bellhousing, but I see what you are saying and agree, the unit would have to be beefy, like a Klune V or ORD Doubler. Seems to me the ring and pinion would need to be up to the task more than anything. I was thinking of this arrangement as a replacement for the very long GM SM465 to NP205 adapter, I'm sure the aux trans could be built shorter than that thing. I also was thinking about my own SM420/NP231 combo that is soon to be an SM420/flipped Dana 300 combo.

Does anyone run a Klune with a Dana 300? How does the Dana 300 hold up?

If the Dana 300 could hold up behind a klune, then it should hold up behind my aux trans. And I've got 3-1/2 of adapter, plus some of he 8" I gain going from the 231 to the flipped 300, so I think the room is there.
 
#11 · (Edited)
Rob Bryce's commanche and the AA adapter are what got me thinking about this.

If you built the housing in a modular design, with different front and rear plates to accept different applications, it wouldn't be that tough. Most swapped in t-cases are using the same or similar patterns, so the Atlas, Dana 300, NP231, Dodge 205 would be covered with one plate, the Chevy 205 with another, and more as demand dictates. The transmission end would be where all the money went, but you'd never need an UD/1:1/OD behind an NV4500 or any other overdrive trans, auto trannies wouldn't work well with the "drop down" theory, so this really leaves the truck fourspeeds, which is what I'm consentrating on here, so, one plate for the SM420, one for the SM465, and one for the NP435. Perhaps all or a couple of the bolt patterns could be combined into one plate.

Maybe there are some gearsets out there already that may be used for this if the housing was built right.

Also, if you built it in such a manner as to require it to be assembled while installing (ie: bolt the housign to the trans, install gears, bolt rear housing to t-case, bolt rear housing and t-case to front housing and trans) you could eliminate any unecessary length.
 
#12 ·
4Bangler said:
Jakester, the Ranger OD or UD auxilliary transmission is installed between the transmission and bellhousing, but I see what you are saying and agree, the unit would have to be beefy, like a Klune V or ORD Doubler. Seems to me the ring and pinion would need to be up to the task more than anything. I was thinking of this arrangement as a replacement for the very long GM SM465 to NP205 adapter, I'm sure the aux trans could be built shorter than that thing. I also was thinking about my own SM420/NP231 combo that is soon to be an SM420/flipped Dana 300 combo.
Sorry I was thinking of the Orbiter or something (which mounts on the T-case output, I think). My bad. But no matter what you do the more gearing (torque multiplication) you have the more stress you put on whatever comes last in line whether it be T-case, R&P, Axles, Front U-joints or wherever you wanna draw the line.

In gearing (as with anything) there's a line of diminshing marginal returns at which the benefits of low gearing are outweighed by the problems that come along with it. I'm of the opinion that the best way to accomplish it is with the fewest moving parts (better reliability) and the fewest components (lighter weight).

Jake
 
#13 ·
True, but this really wouldn't be many more movng parts than a Klune V or ORD doubler while in under drive, and in overdrive shouldn't the stress go the other way, up the drivetrain? I think it wouldn't be any different than running a Gear Vendors overdrive or a Saturn overdrive.

hmmm....Saturn overdrive....okay, how about using Dana 18 parts with a fabricated housing to provide the adaptation between the trans and t-case, with 2.46 gear reduction, and make it so you could bolt up a Saturn overdrive without modifying the drivelines?
 
#14 ·
One thing about lowering the TC... You would have to move the whole drivetrain assembly pretty high in the chassis to get that flat skid plate front to back, covering the trans, aux trans, and TC.

I have a 465/indexed D300 now and the bottom of the 465 is still 1 to 1.5 inches below the frame rails. My skid plate is flat, and flush to the frame, but the trans is unprotecfed. To get the trans up, I'd have to do a lot of raising on the motor, increasinng the COG. I don't think I'd want to do that. Lowering the TC would make this worse.
 
#15 ·
chadl said:
Fun to dream though. Anyone else have any crazy ideas?
Here's my wild and crazy idea. Instead of hanging a Warn/Saturn OD on a D18. I want to hang a four speed transmsssion back there. Gear it such that you have 3:1, 2:1, 1:1 .75:1 or something similar and make at least the 1:1 and .75:1 sychronized so you could maintain the functionality of the warn plus get some good underdrive gearing as well. Naturely since it mounts like a Warn/Saturn, it doesn't add the the drivetrain length at all. This would give me 252:1 gearing and fit in my 80" wheelbase.
 
#17 ·
Grandpa Jeep said:
What? No one wants to shoot my idea full of holes?
uhhh... don't know enough about saturn overdrives, would all those gears work in 4 wheel drive? Uhhh... you have about 2000 lbs of gear boxes under your jeep (Okay that's stretching for a hole) uhhh, you'll have to run your exhaust overhead because the bottom of your jeep will be too cluttered..... uhhhh you'll have to buy gear oil by the barrell full. uhhh your backseat passeners are going to be kicking your last transmission out of gear all the time sinces it's so far back in the chain...

chad
 
#19 ·
chadl said:


uhhh... don't know enough about saturn overdrives, would all those gears work in 4 wheel drive? Uhhh... you have about 2000 lbs of gear boxes under your jeep (Okay that's stretching for a hole) uhhh, you'll have to run your exhaust overhead because the bottom of your jeep will be too cluttered..... uhhhh you'll have to buy gear oil by the barrell full. uhhh your backseat passeners are going to be kicking your last transmission out of gear all the time sinces it's so far back in the chain...

chad
Well thanks for trying. Warn/Saturn Overdrives do work in both 2WD & 4WD, forwards and reverse. Of course the main benefit for me is they don't change the driveshaft lengths at all. There's plenty of room for a tranny where this would go, so that parts OK. Not sure where the shifter would end up, but I think I could build some sort of remote linkage if necessary. Actually, I think I've figured out how to do this using a T-5 and some parts from a Warn or Saturn. I hate to use a T-5, but I can't think of anything else that's somewhat in expensive and has a gear outside of the main case. I suppose an NV4500 would work, but those are way too expensive. One of these days I'm going to try it, but that project's way down on the list. I've got to get my Jeep up and running first.
 
#20 ·
Jason Lockwood said:
Or how about the reduction unit from a Quadra-Trac tcase? It's 2.57 and installs pretty much the same way as the Warn/Saturn except it steps down instead of up.

I've only glanced at this idea, but if it could work????
That's definately a possibility if you only wanted to go lower. Never actually seen one of those things seperated from the transfer case though. Not sure how easy it would be to adapt. It would be cool though and would definately get your crawl way up there. (or is it down there?)
 
#21 · (Edited)
I have often wondered about mating two 4 speeds in series using maybe a female sleeve coupler to solidly link the two?

Also, some mud-only rigs and monster trucks use a homemade single speed transfercase made simply with a few sprokets and some roller chain - this takes up very little space - what about a home made roller chain redution box between the tranny and t-case.....

What about taking the range box off a NP203 and bolting a flat plate to the front to seal it, then adapting it's input to mate to the output of the tranny, and using another tranny output shaft to connect the range box to the original transfercase......should be under 10"????? What about bolting a ½-1" thick aluminum plate to the front and back of the 203 range box (using male/female coupling shafts to link the box) and using the box itself a "thick" adapter plate?

What do you think¿

I really like the idea of an adapter containing reduction planetaries.......could somthing out of a hd tranny work, like a th400?
 
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