91 subaru front final drve ratio

[wiley9803]

I am looking to find the front diff gear ratio on my 91 legacy awd A/T the transmission was replaced with a yard unit that has the wrong ratio I am going to just replace the final drive but I need to know the correct ratio .Thankyou foryour help

[Airgne]

look at the numbers on the side of your transmission and see what they are. this will tell you a code and that can tell you the final drive. google it and youll get it.

[wiley9803]

that would be a great idea if it had the origional trans in it , But like I said .It is a junk yard trans that has the wrong ratio.. Any other ideas on how to find the correct ratio on the front diff that is attached to the auto trans?

[Airgne]

that would be a great idea if it had the origional trans in it , But like I said .It is a junk yard trans that has the wrong ratio.. Any other ideas on how to find the correct ratio on the front diff that is attached to the auto trans?

it doesnt matter. i should be on the left side by the starter.

[wiley9803]

the front final drive is part of the transaxle and it is the wrong transaxle . so the final drive ratio is different on this transaxle from the origional . I need to find out what was origonal for my car. If I use the ratio found on this trans I will end up with the same problem.

[Airgne]

look at your rear diff cover. it should have a sticker on it. i believe all 1st gen legacies non are 3.90 gears. i might be wrong, but it should tell you on your rear diff. than compair the tranny with the rear diff.

[mike-tracy]

the front final drive is part of the transaxle and it is the wrong transaxle . so the final drive ratio is different on this transaxle from the origional . I need to find out what was origonal for my car. If I use the ratio found on this trans I will end up with the same problem.

Not sure what you mean exactly. Airgne had it backwards -
1990-1994 Non Turbo Legacy AWD (AT&MT) - 4.11 FD
1990-1994 Non Turbo Legacy FWD (AT&MT) - 3.7 FD
1991-1994 Turbo Legacy AWD (AT&MT) - 3.9 FD

Use this to decode the sticker on the transmission (on the top drivers side right above the starter)
http://www.main.experiencetherave.com/s ... decode.jpg (http://www.main.experiencetherave.com/subaru_manual_scans/FSM_Scans/engine_&_trans_decode.jpg)

So depending on what you have, and you might have a turbo transmission, then you'll just need to swap the rear diff with one with the appropriate final drive.

[greenspeed]

the front final drive is part of the transaxle and it is the wrong transaxle . so the final drive ratio is different on this transaxle from the origional . I need to find out what was origonal for my car. If I use the ratio found on this trans I will end up with the same problem.

Not sure what you mean exactly. Airgne had it backwards -
1990-1994 Non Turbo Legacy AWD (AT&MT) - 4.11 FD
1990-1994 Non Turbo Legacy FWD (AT&MT) - 3.7 FD
1991-1994 Turbo Legacy AWD (AT&MT) - 3.9 FD

Use this to decode the sticker on the transmission (on the top drivers side right above the starter)
http://www.main.experiencetherave.com/s ... decode.jpg (http://www.main.experiencetherave.com/subaru_manual_scans/FSM_Scans/engine_&_trans_decode.jpg)

So depending on what you have, and you might have a turbo transmission, then you'll just need to swap the rear diff with one with the appropriate final drive.

oach 3.9 fd on a turbo leg, you already don't get an IC then they slap you with a 3.9 in the beast...sad days the early 90's were

[Airgne]

hmm. thats what i get for thinking again. i dont know 1st gens that well, but damn i was way off.

[mike-tracy]

hmm. thats what i get for thinking again. i dont know 1st gens that well, but damn i was way off.
No worries, only reason I know is because I was gonna get a rear LSD for my 1998 5mt Impreza - which is also 3.9 FD. No longer have the car but it's what got me addicted to subies.