Jump to content

Welcome to Ultimate Subaru Message Board, my lurker friend!

Welcome to Ultimate Subaru Message Board, an unparalleled Subaru community full of the greatest Subaru gurus and modders on the planet! We offer technical information and discussion about all things Subaru, the best and most popular all wheel drive vehicles ever created.

We offer all this information for free to everyone, even lurkers like you! All we ask in return is that you sign up and give back some of what you get out - without our awesome registered users none of this would be possible! Plus, you get way more great stuff as a member! Lurk to lose, participate to WIN*!
  • Say hello and join the conversation
  • Subscribe to topics and forums to get automatic updates
  • Get your own profile and make new friends
  • Classifieds with all sorts of Subaru goodies
  • Photo hosting in our gallery
  • Meet other cool people with cool cars
Seriously, what are you waiting for? Make your life more fulfilling and join today! You and your Subaru won't regret it, we guarantee** it.

* The joy of participation and being generally awesome constitutes winning
** Not an actual guarantee, but seriously, you probably won't regret it!

Serving the Subaru Community since May 18th, 1998!

Guest Message by DevFuse

- - - - -

I need coaching on a transmission and differential swap

Transmissions Differentials Swaps

  • Please log in to reply
5 replies to this topic

#1 okamikai


    Advanced Member

  • Members
  • PipPipPip
  • 68 posts
  • San Juan, Puerto Rico

Posted 23 October 2013 - 03:25 PM

Hey guys, this may have been asked before, but I need coaching on this. I have a 98 Forester with a EJ25D and I want to change my transmission for a 5 spd or 6 spd from an Impreza. I've read about the differential ratios and final gear ratios had to match, so what could my options be?

#2 Fairtax4me



  • Members
  • 13,031 posts
  • Charlottesburg, VA

Posted 23 October 2013 - 07:51 PM

If you have a manual trans you can find your current trans ratios here: http://www.northursa...trannychart.pdf

You don't stand to gain much by going with a 3.90 final drive. This would slow off the line acceleration. You may get a slightly lower highway rpm, depending on the 5th gear ratio.

The only option you have for better acceleration overall would be a 4.44 final drive.

If you have an automagic, any manual trans will be an improvement.

#3 okamikai


    Advanced Member

  • Members
  • PipPipPip
  • 68 posts
  • San Juan, Puerto Rico

Posted 24 October 2013 - 12:30 AM

Thx a lot bro, the chart it's really helpful, there few options with the 4.444 Final Gear, ones that caught my attention are the TY752VB6SZ from the 22B Impreza and the TY752VB6EA with Helical LSD, are these fully compatible with mine? its the same year

#4 lmdew



  • Members
  • 3,763 posts
  • Colorado Springs

Posted 24 October 2013 - 06:11 AM

Pretty much any Subaru will bolt to any transmission.  You will need additional parts and there will be wiring to correct so it's not just bolt in and go.

Drive Shaft may be a different length

Trans mounts are different


This is a pretty labor intensive change if your auto trans is working.  If you really want a standard transmission car it may be better to sell your auto and purchase a standard.

#5 MilesFox


    Catch this Fox!

  • Members
  • 10,686 posts
  • Madison/Milwaukee, WI

Posted 24 October 2013 - 07:48 AM

Yhet do bolt up, so if you want to swap a manual you will need along withthe trans:

manual transmission crossmember

front driveshaft(the rear portion is the same with automatic)

matching rear end diff depending on gear.

pedal box assembly

hydwaulic or cable clutch linkage depending on donor trans

you will need the flywheel and the crankshaft bolts that go with it.


a forester manual trans will have a 4.444 gear as well. the forester with the automatic (should be a 4.44) as well

#6 okamikai


    Advanced Member

  • Members
  • PipPipPip
  • 68 posts
  • San Juan, Puerto Rico

Posted 24 October 2013 - 04:05 PM

oh no, I forgot to mention that I already have an 5SPD MT, i just wanted to know if the swap could be made and if it would make any difference in speed and acceleration, I should have mentioned it before  -_-

Also tagged with one or more of these keywords: Transmissions, Differentials, Swaps

0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users