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Need some advice with my 5MT swap on my 98 Impreza Outback


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Hello all, I was going through with a 4eat -> 5MT swap on my 98 Impreza Outback, I needed some advice on a few things so I can move forward.

 

I recently did the research and wanted to make sure I have all my bases covered before doing the work...

 

So for some background information, I have a late 97' Impreza (effective MY98) with a 4eat, high mileage of course, at 240k and finally the trans is choking up.  I would like to swap in a 5MT, and after searching around, I found a donor car at the junkyard, a MY99 Forester. I tell the guys to take care of the driveshaft but they smashed the metal around the center bearing. Oh well, turns out that due to the Forester's body lift, the center bearing is also spaced higher to account for that lift - which means I need to change the center bearing with an impreza one.  So, on to the first question - should I just cross my fingers and replace the center bearing with an impreza specific one?  I can't really tell if the driveshaft is bent until I throw it on. Or, should I bring the whole thing to a driveshaft shop and ask if they can make a one-peice?  If I was made of cash I would just buy a new CF driveshaft and call it a day, but I guess you could call me "tight" :D

 

Second, I wasn't able to get the mileage from the donor car because the cluster is electronic. (shoulda brought a 12v pack) but I don't have any experience with transmission quill repair or inspection.  There are sleeve repair kits out there, but how would you know if you need one?  Need a second opinon. I would say the wear doesn't look bad enough to need one?

 

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The car at the junkyard seems to be totaled because of a quarter panel collision, not even that bad!  (well, I hope the transmission isn't DEAD.) Which leads me to my next question.  The extension housing / tailshaft housing seal has some damage but I can't figure out why.  it looks like the driveshaft was grinding on the housing seal area, but why?  Maybe the rear end collision shifted the subframe enough to push the front end of the driveshaft into the tailshaft housing?  It looks as though I can clean up the area and replace the seal but it might be a chore because there is no chamfer to guide the new seal in.  Would that be an indication of a problem or should I be okay?  What is odd is that on the driveshaft yoke, I do not see any evidence of grinding. Wtf.  :/

 

26450.jpg

 

The transmission crossmember is another screwup.  The forester has spacers all over.  I noticed that the forester crossmember has spacers on it, could I take an angle grinder to it and remove them, or do I have to buy an impreza specific piece?

 

And lastly, any simple checks to make sure the trans is not toast before I bolt it up?

 

Thanks for the help.

 

 

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Did some research, looks like the trans should be O.K as long as the endplay on the output shaft is within spec.  Looks like the donor car had the rear subframe shift closer to the trans which pushed the driveshaft into the tail housing. Did some minor "dressing" to the area and the new seal went in okay.

 

Need to find a place locally to lengthen the driveshaft as the AT driveshaft is too short (expected) but not too sure about the crossmember. All the 5MT swap articles suggest the forester crossmember is different, but a quick mock-up of the crossmember without the trans seems like it fits okay. I do notice spacers welded to the crossmember on the forward-most bolts, but the crossmember bolts up perfectly. There must be something different about the forester specfic crossmember that I don't fully understand.  Maybe I will find out when the actual transmission is installed.

 

Found the answer to my first question about the transsmission snout wear; if there is no noticeable "step" worn into the transmission snout, the transmission is still servicable as is and does not need an aftermarket sleeve setup.  The replacement sleeve repair kits are only for those transmissions with grooving or deep material loss in the snout.

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  • 5 years later...

5 Year update, lmao. Figured i'd add a couple notes for reference.

Went with a Dorman Reman Driveshaft, great quality, no problems, balanced well and has grease fittings - sweet. Center Bearing is included IIRC because I can't recall anything about that part of the install. Note: I wouldn't recommend trying to rebuild the driveshaft / u joints yourself, as the u-joints are not designed to be serviced, and while they share similarities to the Nissan drivetrain and *can* be serviced (so they say) , I learned they are a royal b^tch to replace and do require a lot of specialized skill to replace.  NEAPCO makes replacement bearings, and as much as I wanted to save a buck and do it on my own, tried and decided it was probably a waste of time. :D  YMMV, there area a few YT videos and I believe @ the time, there was a very informative video of some dude that was repairing a HONDA driveshaft that helped show what needed to be done.

Did not need to do anything extra to the transmission snout, ie: snout sleeve.

My 98 was a Phase 1 engine - 4 bolts + 1 stud for starter. Donor trans was a Phase 2 w/ 8 bolts, (2 for starter). Trans bolted up no problem, however instead of drilling+tapping a hole to receive the (1) starter bolt needed, I left it be.  Works fine, I added loctite to the single existing bolt just in case. Torsional loads are not a concern because the starter has a machined lip that will contact the bellhousing to support any torsional load if the starter were to dislocate / shift.

Whole reason for 5MT swap was that my 4EAT was tired, and obviously had some strange shifting patterns and habits that could only indicate imminent failure (ha ha).

I was in a rush, and with a stroke of luck, there was crashed Forester @ the local junkyard, so I jumped on it, since I needed to fix it quickly anyway.  I could have sourced a more *desirable* transmission and gone about the whole process differently, sure. But, ahem my excuse = lazy+no time.

Anyway, the 4eat differential ratio was a 4.11, so lucky me, the donor Forester 5MT apparently had a 4.11 final drive as well, which definitely worked out in my favor, too - I didn't have to muck with the rear end.

Personally, I think it really worked out, in a weird way.  I guess i'm happy with it, all things considered.  The donor transmission in the Forester has a shorter 2nd, 3rd, @ 4th gear ratio compared to most Impreza gearsets / 3.9 Final Drives except the RA models, which is pretty neat. Coupled with a 4.11 Final drive, city drivability seems improved. I mean, with 137 horsepower on tap, gearing helps a ton. *wink wink*

Only caveat is that the VSS gear on the front differential is geared for the Forester tires - (larger rolling diameter) and cannot be changed without some type of sophisticated electronic DIY VSS speedo calibrator converter custom deal or, replacement of the actual gear (ie: take it all apart  ^_^) I'm lazy, so I chose to leave it and calculate the offset if I wanted to know the real story on things.

Cheers.

Hiya_edit.jpg

Edited by slowpoke
Grammatical Error
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Thanks for the update. 

Interested what your Manual Trans ID was (TYxxxxxxxx) or the exact year Forester it came from? I may be needing one myself. I know there are many options, but nice to know 'for sure' what someone else installed.

 

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  • 3 months later...

wtdash:

If my memory serves me right, you need to be particularly careful about the final drive of the transmission you're swapping in, since a mismatch would simply blow up in short order. :D

So for what it's worth, this is what I jotted down from the donor car -

 

1999 Forester "L" 2.5L SOHC

Applied Model: SF9BY3M

Option Code: PA

Trim Code: 84D

Engine Type: EJ253AWZVB

Transmission Type: TY755VC1AA

PUSH Type Clutch

 

Also, my Imp. Outback is weird.  It is a late model 97, effective model 98, 2.2L single port.  I guess not quite the unicorn, but around here they are kinda rare.  Most of the people around here just used them and threw them away after 15 years of surf sessions.  I actually like my car, so I try to maintain it. :D

BTW, when I did the swap, I figured what the heck, everything is apart.. I opted for a 10.5LB ACT Prolite Flywheel. + Stock OE Style Exedy Clutch.  It makes the car a ton more fun to drive (IMHO how it should have been from the factory), especially with the 4.11 Final Drive.  My notes tell me I used an ACT #600700 which, surprisingly, is the same as a 2013+ BRZ/FRS application.  Whatever the case was, I called ACT @ the time and they asked me a bunch of questions which led me to find the correct flywheel that would work.

The only caveat is that you probably want to make sure you have a crank timing guide (Automatics did not come with one - very important as your timing belt will skip = bent valves) - and also converted my timing belt tensioner to the older 2-piece hydraulic setup with the piston and idler separate due to the flywheel. The older setup is a much better design and will resist "hooning" a little more with the light flywheel.  You have to buy the aluminum tensioner bracket to convert to the older style, as the mount is different between the two.  I also noticed that the Forester has a shorter 1st gear ratio for whatever reason.  Makes things more interesting, huh.  As I stated, what is annoying is that the VSS / speedo gear is made for Forester diameter tires, so if you plan ahead somehow, you might want to address that issue before the trans is installed.  My speedo reads about 5mph too high, and for purists, that also means other things as it technically skews the "actual" chassis mileage by a percentage, etc..  I think there is a way to convert / modulate VSS signals in between the VSS and cluster, but probably too complicated for me.  I tried some bogus converter at one point, and it didn't work for me. LOL

YMMV, but this is my personal experience with it.

I hope this is of some help, cheers :D

 

Edited by slowpoke
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