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Need help understanding the divorced t-case mod


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I've been reading up on the divorced transfer case mod and was left a little confused. How does this work? What parts are needed?

I'm looking to be able to crawl well with some 26-28" tires. Would this even be a cost effective idea or should i just leave the gearing stock. The wagon came with the D/R and 3.9 in the diffs.

 

Thanks for helping me out

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From what I've read in here about the divorced t-case, you dont really need it if your going with 26 -28 inch tires..

stock tires are 25 inch.

 

If your going 30+ inch you'd need the t-case.

 

As for the mod, I'd imagine a driveshaft comes off the T-case to a seperate front diff just like on a pickup

As for the cv joints, I'd imagine there must be a mod to put stub axles on the diff and then the CV's would hook to that..

 

Rooinator is this correCt?

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It's not a small task - you need a complete reinforced subframe to hold all the components - custom drivelines - custom steering linkage, and custom shift linkage. I'm probably missing a few things. There's a reason only three have been built so far (that I know of).........

 

Also - the crawl ratio is good, yes - so good in fact that you end up breaking other components - like diffs and axles.... the added torque is a lot for the stock soob axles and diff to handle.

 

GD

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I haven't done this conversion (yet perhaps) but I'm not sure you need to mess with the subaru shifters as the engine stays in stock location to make room for the extra diff underneath. It's still a huge job anyways no doubt about it.

 

tranny d-shaft tcase

------------, ,---------,

1.5:1 I--------------I I

_______/ I 2:1 I

,____ I I _____

I \____ __-- I______I----___ _____/ I

I_O_______I---- -----I_______O__I

 

front diff d-shaft d-shaft rear diff

 

how the heck do I make ascII art work? so much for that

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stock tires are 25 inch.

 

My stock tires were only 23 inch.. my pugs with larger tires are just barely over 25..

 

I can think of 4 people right off the top of my head with the divorced T-case.. is this the wave of the future?

I would be happy just to find a D/R down here for a reasonable price:mad:

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If your going to have this vehicle be your daily driver a divorced T-case would not be a great idea.:(

 

If your going to put on 26-28 it will work as a daily driver but your going give up your gearing. Calebz right on the stock tire size.:rolleyes:

 

Do I smell clutch? :eek:

 

I'm doing a 26" but I have a #1000 weight reduction, so I may have a net effective ratio similar to what stock was. I hope:confused:

 

There are no easy solutions or we would all be doing it. You need to access your needs and see what going to work the best.

 

Good luck,

Glenn

82 Summer, almost wired...........

01 Forester, bent but not broken

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Thanks for pointing that out Caleb. Stock tires are only 23". You can run any size tire you want on your Sube. However, the larger the diameter the worst your gear ratio ends up being. Example, a stock ratio with stock tires is 3.90. By adding 185/70R14's you change the gear ratio to 3.75.

 

The idea behind the transfer case mod is to lower the crawl ratio. If you are not into REAL hardcore off-roading it will not do much for you except drain you bank acct. It will add more pressure to the rest of the drive train. But it allows you to basically get out and walk next to your rig on the trail while it is running/driving.

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yeah, i wasn't really looking into an install. i was just curious. i would just love to see the looks on pople's faces when i drive over their Geo in a station wagon.

I plan on using 27-28" Swampers or Goodrich Mud Terrains. Whichever is cheaper. I'll still probably be ble to climb a Geo with this setup and my D/R. Buddy of mine when told to watch it or i'll climb his Fiero, "If you can ever catch up to me." Damn, the truth hurts. I need a WRX engine to stuff in my 88. Problem solved.

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what year/ modle subys is this mod applicable to? i dont have a front diff, just a trans with some cv's and a rear driveshaft. but it also isnt a d/r, just a push button. i had an 84 dual range, but honestly dont remember seeing a front diff. is that something you have to make. like take another rear diff and stick it in there with some fabbed brackets? but then wouldnt the revolution be backwards?.......im confusing myself:-p

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that's exactly what it is. a rear diff put in front with a custom subframe lift, etc... the rotation isn't different because the rotation coming out of the t-fer case would be correct....

 

in the normal sooby transaxle, there is an integrated diff inside the case.

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So with the T-case mode people are breaking diffs and axles? I guess the stock tranny is a solid unit? Then again is anyone runnig a T-case mod with an EJ20T or EJ22T?

 

I'm getting more and more into the idea of building my EJ22T powered Suckzuiky axled Justy, but I wish there was just a tranny with no front diff that would bolt up to the EJ motor?

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thats what i thought by that sweet diagram.(no pun intended). wow that would take some work. how do you het the axles and spindles to line up. drop the strut. but then what about the control arms. that would take a lot of fabbing. how well does it craw? pretty well.

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  • 1 month later...

I am working on a fun shop project that will incorporate the existing engine transaxle assembly from a GL wagon into a custom tube frame buggy using a Sammy t-case.

 

The questions I have regarding this (its good to find a thread on people already trying similar mods) is:

 

1. Without knowing too much about the Soob setup...what happens to the existing splined outputs on the front end that are no longer used?

 

I am assuming/hoping that I can get the original equipment to output in both H/L out the rear driveshaft and feed that into the t-case. Is there a thread indicating the ability to get a rear output only out of the stock drivetrane?

 

Meaning: I want the existing front output to cease spinning. I want all available torque/power going out the rear.

 

2. Also - the tranny is slipping out of 3rd gear. My assumption is there is some kind of detent spring or other retention mechanism that is worn or needs adjustment/replacement. Can anyone reference a writeup/solution/thread on this?

 

Thanks!

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Welcome to the board!

 

If I understand things correctly....

Since you don't use the front transaxle (consequently they would take no power away from the engine) all output power would be transfered to the driveshaft.

 

My suggestion is use the old transaxle cups as a PTO for a generator/welder or Winch? A PTO could be real handy along the trail? Mudrat has some ideas on this.

 

On your tranny...

I have the same problem in first when I lug it. Folks on the board have told me that its most likely a syncro that is messed up and causing the problem.

 

Anyone else?

 

Glenn,

82 Summer, SubaruHummer.......

01 Forester, Jealous.........

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Thanks for the response.

 

I have a feeling I'll be hanging out a while as we get into this project full-force.

 

It should be obvious...but I'll admit it anyway. I have very little familiarity with Soobs.

 

Is your suggestion to just run it in 4wd and ignore the front outputs? Is this how others have done it? For some reason I thought getting it to run in RWD only would be ideal. I suppose if I were to really think about it...so long as there was not a center diff...its no big deal.

 

I was hoping for an easy fix on the tranny. I suppose in this case it is good to have access to a host of donor vehicles...

 

Are there any links with some creative use of the extra outputs? (perhaps Mudrat has a site?)

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That set up in Mudrats Beast, was that with a 4EAT or just a 4AT/3AT? It's funny but I just thought of the possibility of using a 4EAT in a RWD conversion instead of a 5 speed. With the auto you can remove the FWD peices to make it more efficent and create less heat than normal.

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