I have done my homework and I know the 4th gen rearend will go in without modifying it but the question I have, Will the tires rub the fenders when i am going around corners hard? I have a 91 GTA when i replaced the diff fluid I noticed that someone put a open diff in my car. I did get a 4th gen rearend yesterday the gears are 3:42 Torsen.

 

I've got one in mine with the stock tires and they dont rub, only with 4 people in the car and going over bumps in the road

 

Was it easy to swap out? Did you have to remove the axles to put the backing plate in for the brakes? There is nothing for brakes on the new rearend I will have to install my disk brakes from the rear end thats in my car right now. I have never taken my car apart that far before.

 

pretty straight forward swap, hardest part is getting bolts loose that are rusted, other then that jack up the car, put towers over the frame, removes wheels, shocks, torque arm, pan bar, A arms and that pretty much it, if you already had disc brakes you mind me asking why your going with a 4th gen rear

 

someone took out the original diff and put an open diff in. I traded a set of headers I had that wasnt going to fit in my car for the 99 t/a ws6 rearend. I dont know much about changing just the diff never done it and afraid that i wont get it right. I called the dealer they said that it wont work in my housing because it has trac control. I have a limited budget so cant afford $900 for a new one from the dealer. I am trying to get everything right for my budget

 

Can just replacing the diff be done?

 

yes, but it need to be done professionally. Setting up the gears requires special tools, and if its not done right, it will whine and have a very short life.

 

Traction control doesn't matter - since your car doesn't have the traction control computer, there won't be anything hooked up for the traction control,. therefore it simply won't try to control traction, and thus be like any other rear end without traction control. The 4th gen rear will swap in as is (except for your brake issue since your 4th gen rear has no brakes on it).

 

I talked to my neighbor and he asked why dont i just use my ring and pinion set that belongs in my car and just replace the diff I dont know much about rearends so I didnt think the ring came off the diff. Will this work and are they compatible so I dont have to put the 3:42 in and I can keep my 3:23. I know I should know all this but I dont know rearends and I have never had to work on one. Everyone has to learn somewhere, I would like to learn from people that know these cars, know what they are doing. thank you very much.

 

You could do that, they come out. But again - as mentioned already - need special tools and knowledge to swap gears - not worth the expense you'd pay a rear end shop.

Very little difference between 3.23 and 3.42 - might as well save the trouble/expense and just swap the entire rear in. You'll get a tad better seat-of-the-pants feel with the 3.42, and will loose a tiny bit of mileage - but not enough to justify the expense of swapping gears.

I have no idea about the brakes - if you can easily swap your brakes onto that 4th gen rear, then do it, and install the 4th gen rear as is and call it a day - you'll never notice anything but a very small difference in mileage and a very small icrease in off the line times.

 

I just took the torsen diff out of the 4th gen rearend glad I because one of the pinion bearing were messed up. What speacial tools do I need to take the ring gear off and put my 3:23 ring on. I just see a bunch of 19mm bolts. I really want to learn how to do this. this backlash seems easy to set up 6-10 thousandths Is what it needs to be I read. Do I have the Zexel Torsen like what you have?

 

The ZT rears were later years 4th gens I believe, I really have no clue.

I don't know anything about swapping gears and such - I'm smart enough to leave differentials and tranny's to those that know what they are doing.

 

The following link will provide a how-to on setting up gears:

https://www.thirdgen.org/forums/tran...axle-gear.html

JamesC

 

JamesC thank you for the link wish i had it before I took the new diff out I didnt mark the shims left or right and didnt realize the reverse threads stripped out one bolt and hole so wont be selling the 3:42 gears but atleast I learned before i ruined anything I am going to be using. I will have 2 sets of shims I hope I wont have to get more but oh well if i have to