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changing RX from 3.7 to 3.9 -got questions-

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Alright, so i am going to swap my tranny, rear end, driveline, and axles (tranny took a dump on me in december) from the RX AWD 3.7 drivetrain to the GL dual range 4WD 3.9 drivetrain.

 

1) the biggest question i have is: Will the 3.9 axles fit into the hubs of the RX without modification, after the 3.9 tranny and rear end are in the car?

 

2) Will i need to snag the tranny cross member from the parts car or will the RX crossmember bolt up to the 3.9 tranny?

 

3) Will i have to modify the driveline to fit inbetween the 3.9 tranny and rear end? (I am almost sure this is a no because the wheel base is the same between the RX and GLs)

 

4) Is there going to be any problems with the turbo clutch pack/flywheel fitting in with the 3.9 tranny?

 

5)and last but not least: Is there anyone in the Salt Lake City (more specifically Kamas) area that wants to get their hands dirty on the 23-27?

 

Well, i hope that covers all that i needed. Feel free to add in comments, tips and tricks to the thread....

 

Hopefully this swap will go fairly easily....yea right....like anything is easy in my life...lol

 

thanks in advance for any and all help...

If you grab and EA82 D/r 5spd, then it will virtually bolt in with very little mods. The only problem that I see is if you have the 25 spline axles in it now, and the D/r has the 23 splines. Other than that it is pretty much just plug and pray. The case of the FT and D/r tranny are pretty much the same externally.

Just get the transmission, diff, front axles, and shifters and you should be good to go.

all righty I guess I can step up here and put my $.02 cents in...

 

1. The RX hubs are the same as the GL hubs. The only difference in the front axles is yes the RX DOJs are a 25 spline whereas the nonturbo GL axles are a 23 spline

 

2. The crossmember is the same...

 

3. Drivelines are the same between them. I currently have a GL wagon driveline in my RX from doing the auto to manual swap.

 

4. The turbo clutch kit will fit, no worries.

 

5. Sorry Donny, I gotta work man or I'd come and help ya out:)

  • 2 weeks later...
  • Author

Alright....I did it. And this is what i learned....

 

A tranny is not a light object. Tends to not want to be picked up, come out, be put in, or be manhandled in anyway shape or form.

 

The sun is hot...Fingers and self calming techniques stop working with too much sun and a lack of water.

 

The more you swear and cuss and tell a car that you will laugh as you roll it off of a cliff, the more things go your way.

 

and last but not least...if you don't put in the two nuts that hold the rear end to the diff hanger...funny things happen...people honk and flash their lights at you. (i think the lack of water and too much sun heighten stupidity)

 

But seriously, the swap went way easier than i thought it would. I got the parts mentioned above, and everything went smooth as karma would let. The gear change is for the better i think. I didn't loose any highway speed that i use, and the bottom end is much better than with the 3.7

 

i also found a LSD rear diff at the junk yard for a very cheap price. can't complain one bit about that.

 

So the RX is on the road once again....I didn't think i would ever say this, but i like driving my run down RX more than my Impreza....who would have thought.

 

If any of you have any questions, post them up....it is all fresh in my mind, so i might have some input...

 

take it easy....im going to bed

 

harpua

Hello, i have a cuestion, if any can tellme, what is mi car model, mi subaru whas buy in 1987 but the document say the car is 1988 year, i think thats is model, well mi car is automatic 4x4 turbo sedan, have sunroof, a/c, is full, but in any place say whats is your model.

 

thanks and escuseme for mi english, it´s so bad but in mi country any know about this car, than again

Very often new year models are released early.so your 88 could have been bought in 87.Welcome to the board.Dave

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