3 bolt ring and pinion in 4 bolt

[TREV TEC]

I found a auto 3 bolt rear, I am wondering if anyone has tried to put 3 bolt gears in a 4 bolt diff?

 

[-red97rum-]

I know it can be done, but I've never done it personally. I remember reading a few threads on it a long time ago because I was going to do the same thing. But I gave up because I ended up sourcing a 4 bolt auto rear.

I've seen a few threads on the ecmlink forums that say only the ring gear needs to be swapped, however, I can't confirm that %100

http://www.dsmtuners.com/forums/drivetrain-tech/187679-can-my-3bolt-ring-pinion-go-4-bolt.html

http://www.dsmtuners.com/forums/drivetrain-tech/469116-auto-swap-rear-end-axle-compatibility.html

http://www.dsmtuners.com/forums/newbie-forum/299946-4-bolt-3-bolt-rear-end-question.html

It can be done, the only thing to worry about is shimming/pre-load from what I've gathered. Those specs should be available in the FSM. You may want to shoot an email to Jack's Transmissions or PM some members that are more experienced with our drivetrain. Tim Zimmer (twicks69) comes to mind.

This thread has some good info:
1G Rear End Pinion Shimming

If you end up getting it done, please follow up and post the results and specs you used. My auto rear has been whining for a while now and I've been tempted to do the same thing so I have a spare on hand.