donor cars for 5mt into 4EAT tranplant question

[Adam Lee]

Hello, after thinking more about it, I would like to hear some more about swapping the 5mt trans/tranfer into my 94 Leg Lsi wagon. The 4EAT will probably duke it out for several more years before the binding becomes unbearable, but I really don't want an AT anymore anyway.

 

Which platform vehicles, years, and specific trans/transfer packages are direct bolt-in for the 91-94 body?

 

And please, explain the 2 different transfers to me, as far as which ones (pushbutton or d/l) were optional for this package. Which one will I run into more often?

 

Should I be looking for a wrecked 91-94 Leg with intact 5mt/transfer, or just keep surfing junkyards & message boards? Not really seeing much.

 

Any notes/ideas from folks who've gone this route would be appreciated, either on/off board, whatever.

 

Trying to see if I can justify doing this versus buying a buddy's old 88 SAAB turbo 900 16v......I ran with the SAAB's for a number of years. He wants to sell me the SAAB for 1500, and if the 5mt swap is too time-consuming and expensive, I may just sell the Sube as is and invest in the SAAB.

 

ok, time to get back to school....40 min till my kids are back from Art class! (I'm a 3rd grade teacher)

 

Ciao

[Legacy777]

Have you read my write-up?

www.surrealmirage.com/subaru/swap

 

All of the 90-94 legacy tranny's will work.

 

Your 94 4EAT has a 3.90 final drive ratio. The 91-94 turbo legacies were the only ones with that final drive ratio. So unless you get one of those transmissions, you will need to swap the rear diff too.

 

Dual range transmissions were not available on the 90-94 legacies.

 

Your best bet is to find a donor car, that way you have everything, and don't have to piece-meal the parts needed.

[Adam Lee]

Thanks, I took a look at your photoalbum and guide to get a feel for the work involved.

 

I was hoping that I could get a real brief explanation of the mechanical differences between the transfer unit used with the 5 speed, versus the transfer unit used with the automatic.

 

Essentially, I wanted to ensure that what we're working with here are two completely different beasts.

 

If the 4EAT "awd" unit works via hydraulic fluid and clutch packs, is this essentially a viscous coupling style transfer?

 

And would the 4wd unit sending power to the ft/rr diffs on the 5-speed cars be more of a mechanical transfer?

 

I have absolutely no books (other than Haynes) so I really don't have any quick reference to walk me thru it. Plus, since I just started another school year 2 weeks ago with my 3rd graders, I'm more than a little spent as of late.

not too much time available for gearhead activities....

 

Is the 5-speed that mates with a standard 2wd legacy the same housing as one destined to live with a 4wd legacy, but just with a different tailshaft or something?

 

If that were true, then theoretically I could start collecting generic 5-speeds and keep an eye out for a transfer case/4wd tailshaft extension....knowwaddimean?

 

adam

[Legacy777]

The AWD systems on the auto and manual trans are completely different.

 

The automatic uses clutch plates, and a hydraulic solenoid which actuates the plates like a typicaly automatic transmission.

 

The manual uses a viscous coupling attached to the center differential. There are inner and outer plates in the coupling along with a silicone type material that becomes more viscous as the plate "shear" it.

 

I've got technical scans, but one of the drives on my server is crapping out. So once I take care of it tonight, I can post those scans.

 

The rear housing is different on the FWD 5spds, however you really don't see many of the rear housings and transfer sections of the AWD trans floating around. I would just try and find a complete AWD 5spd.

[Legacy777]

Here are the scans I was talking about.

 

This describes the AT

http://www.main.experiencetherave.com:8080/subaru_manual_scans/FSM_Scans/AWD_transfer_system1.jpg

http://www.main.experiencetherave.com:8080/subaru_manual_scans/FSM_Scans/AWD_transfer_system2.jpg

http://www.main.experiencetherave.com:8080/subaru_manual_scans/FSM_Scans/AWD_transfer_system3.jpg

 

MT

http://www.main.experiencetherave.com:8080/subaru_manual_scans/FSM_Scans/AWDMT_description.jpg

 

Center diff

http://www.main.experiencetherave.com:8080/subaru_manual_scans/FSM_Scans/MT_centerdiff1.jpg

http://www.main.experiencetherave.com:8080/subaru_manual_scans/FSM_Scans/MT_centerdiff2.jpg

http://www.main.experiencetherave.com:8080/subaru_manual_scans/FSM_Scans/MT_centerdiff3.jpg

[Adam Lee]

gracias, my friend...those scans made things much more clear.

If I can ever run across a 5mt/AWD wreck, 91-94 wagon, I'd be set....partial to my 94, since it's an LSi and all the accessories & sunroof actually work....and the body is good.

[NoahDL88]

don't quote me on this, but i think you can also look for the sedans, at least that's my hope, i'm putting a 91 Legacy 5mt into a 96 OBS.

[Adam Lee]

any folks hear of east coast soob junkyards/recyclers who are reputable with component sales?

 

in other words: good yards that sell fairly decent whole trans/engine packs, etc...already removed from vehicles?

 

there are a million of them, but I always appreciate a little inside info on the "good guys"...

 

ISO 5spd MT and AWD unit for a swap into my 94 Leg Lsi Wagon (4EAT & bad transfer unit)

 

thanks!

[Gnuman]

OK, waitaminute. When you get torque bind (in an automatic transmission) what part actually went bad? if putting the fuse in solves it, I suspect that it is not the Duty Solenoid, but I may be wrong. From the looks of this, teh fuse turns the Duty C to max, disengaging the clutchpack. when you have torque bind, it looks like the clutchpack is always engaged (otherwise the rear wheels would be spinning freely, and there would be no bind). So if Duty C fails, giving no release to the clutchpack, you get torque bind like symptoms. Sopmeone please tell me where my logic fails, or if there is a simple fix to the torque bind without replacing the whole extension. What part in particular is the one that fails?

[Legacy777]

You're correct. If inserting the fuse remedies the torque bind. The problem is with the clutch packs. If inserting the fuse doesn't do anything, the duty c solenoid is most likely bad, and the clutch packs could be bad.

[Gnuman]

You're correct. If inserting the fuse remedies the torque bind. The problem is with the clutch packs. If inserting the fuse doesn't do anything, the duty c solenoid is most likely bad, and the clutch packs could be bad.

 

But how are the clutchpacks bad? If I understand the diagrams, the clutchpack is a hydro acuated friction clutch, and burning them out would mean no friction, causing a FWD only condition, as no drive is transfered to the rear wheels due to the lack of friction in the pacs. or is the usual failure a bonding of the clutch materials (friction heats them up causing them to "weld" themselves together)?

 

One more question: is there a good way to check the AWD function of an early 4EAT? I know of one where the front wheels slip when driving up ramps. when I put the car on jackstands (all 4 wheels up) all 4 wheels spin, but the rear ones can be stopped (by using the parking brake) without the frront ones stopping. the same is true of the front wheels (the rear ones do not stop when I jam a block under thefront wheels to stop them). what other checks can I use to tell me what is going on with this tranny?

[Legacy777]

Typically clutchpacks go due to not changing the fluid regularly. Dirt and other junk build up on them. I suppose you could remove them, sand them down, and put them back in, but for the effort of removing everything....put new clutch plates in.

 

Try driving in some gravel, or stomp on it when it's wet. After driving a FWD for 8 years I can tell you, in those cirmstances you will peel out if it's only FWD.