You'd have to check the rpo codes in the glovebox, but it might not have the g80 posi unit. The cheapest and easiest thing to do, would be to pull the gears out of a 7.5" rear and put them in yours. Get the ring, pinion and the posi. I'm pretty sure all bravadas came with 3.73 gears and posi's, but I could be wrong on that. Once you pull them, or even before, look into a rebuild kit for the posi. Really, in all honesty, if you have a posi and 3.42 gears already, the 3.73 gears may work with that, but I'll let someone who knows more about that to chime in on it. Got any pics of your ride? We like pics here. I think you should look into that rough country kit you asked about in the lifting section and a 2" body lift. Fack gears, man, if your only going up to 31's you'll be fine for awhile. If it dosnt perform like you want, save up 300 bucks and buy a set of 3.73's later on.

 

+1 on what Sickman said here. It used to be encouraged and almost policy to put a description of your truck in your signature (year, doors, 2wd vs 4wd) to help people give better info. It's a really good idea.

From what you were asking, and the way you were talking I thought you had a 4x4. You don't want a ZR2 axle if you have a 2wd. It will be way too wide. If you want a wider axle get one from a regular 4x4 Blazer or Bravada and check the RPO's in the glove box to confirm the gearing and if it has the G80.

 

If he already has the g80, wouldn't it be possible to just take the ring and pinion? Seems simpler and easier than trying to find a 2wd axle with a posi and 3.73 gears.

 

I'm not sure. My understanding is that it's not as simple as simply swaping the new ring & pinion in. I believe you have to set lashing or something like that? I have zero experience with this, so I'm not the best source. Hopefully someone with more experience can chime in here.

 

Gears are not an easy install, if you have no experience with it you should get it done by a shop which means a good chunk of change. They have to be set up properly or you could easily ruin the all the internals. Swapping the complete diff is much easier for the average person to tackle.

 

so would it cost alot to get 3.73 gears put in a 2wd?

 

My guess is it would be in the $4-500 range for just the labour. You'd have to go get some quotes to know for sure. I was charged $600 for my locker install, but it shouldn't have been that high... that's a rant I won't get into though lol.

 

Well check pick and pulls. I don't think it'll be as bad as you think if your looking at 30's or even 31's with a 3.42 and a g80 already. 31 inch tires are 2 inches over 235/75r15 on my 4x.

 

I see the RPO codes on here for the ratio but can anyone tell by the RPO codes as to what size the diff is. PS every time I see a new RPO code on here I make a mad dash for my 97 blazer 4 door 4WD only to bring more bad news . I don't have the g80 and I have the gu6 3:42 gears and not the 3:73