i can? cus my diff is 3.42 gears and it has a 12 spline pinion and the other one was 3.73 and it had a 11 spline pinion so could i swap them? and would that **** w/ my front at all? ( what i mean by swap is take the carrier out and just swap them and not the pinion's?)

 

Take the pinion that's on your current diff, and put it on the G80 out of the Bravada.

If you just swap diffs without swapping gears, you're gonna blow stuff up when you use 4x4 if your wheels have any sort of traction...

 

The pinion is the input shaft/gear. The ring is what you will need to swap from your diff to the 'new' diff. You shouldn't need to pull the pinion out of the axle housing. Setting up the 'new' diff will be the challenging part if you haven't ever done it before.

 

so ur saying that if i just take the carrier and ring gear out of the other rear and jus put it in w/ mine now it would work? so would that change my gear ratio to back to 3.42 rear instead of the 3.73?

 

Ring gear is what I meant...

You're going to need the carrier from the Bravada axle... The G80 carrier is different from the open diff carrier.

Take the ring gear off YOUR diff, and put it on the G80, and that'll keep your 3.42 gears.

 

Don't know where you got that idea from... You need to swap the ring gear from your diff to the 'new' diff as I stated in the post above. The ring gear is on the diff. The pinion is in the axle housing. The pinion can stay put, but the ring gear most definitely needs to be swapped.

Now, let me say this, if you are having trouble at this stage, do not go forward with the swap on your own. Setting up a rear end to run right is not for the faint of heart and will take several attempts to get everything correct. You can do MUCH more harm than good by swapping things out and not getting them setup properly.

This might help:
Setting up a Differential Ring & Pinion - thedirtforum.com
Don't Let Her Rear End Scare You (4 pages) - streetrodstuff.com

From these two articles you will find that it isn't a simple process of swapping parts. Also note that not a lot of what is done in the SRS article apply to the rear axles in our car. This primarily pertains to a Ford 9" setup in terms of how to set the proper pinion depth.

 

well today i took the g80 rear out of the other diff swaped ring gears and when i went to put it back in it was kinda tight and then i got one side of the axle in and b4 that i couldn't turn the pinion by hand so wat did i do wrong?

 

You have to make sure it's shimmed properly... Everything has to be aligned right.

 

how else could i shim it then if i used the shims that i got w/ that rear from the diff?

 

If those shims didn't work... try the shims that you took out of your diff...