I just blew up the R&P in my rear end on my 94 Blazer Full Size and I found someone parting out a 96 Suburban and a 97 Pick up 1500, I would like to know if they have the same rear ends and if the differential would work with my truck, thanks for all your help!

 

I'm sorry I don't know for sure if the diff assemblies are the same, but I just wanted to tell you to make certain that the rear diff gear ratio in the doner matches the front diff ratio...If you're working on a 4wd that is. If they are different ratios...you will have BIG problems. The only way to know for sure if it will FIT in yours, is to measure the diffs......from the center of the flanges for the leaf springs and from backing plate to backing plate.

 

I don't need the WHOLE assembly, I just need to know if the actuall rack and pinion is the same, not the axle housing. And I know I need to match the ratios too. Thanks. Do you happen to know the ratios on a 96 Suburban?

 

You would need to check the RPO code listing on any of the vehicles concerned. I think that your blazer and the 1500 pickup have the 8.5" rear ends, but the suburban may be larger due to the added girth.

Seeing as how the wheel base is the same between the vehicles being discussed, why not pull the whole axle out and swap it (providing the ratio's match)?

 

Kind of hard to give you a straight up yes or no answer on this one.
1/2 trucks and some 3/4 tons trucks used the same rear axle (10 bolt). 3/4 ton trucks and 1 ton trucks also used the same rear axle (14sf). and the 1 tons also used a stronger axle (14ff). To get a right axle you would have to know whcih vehicle you have, and what the donors are 10 bolt, 14sf, or 14ff? All three of them have different size Ring & Pinions.

Once you figure that out then you need to figure out if the Ring & Pinions are the same. The easiest way to do that is by the codes in the glove box.

Now if your getting the parts from a salvage yard. They can help you match the axles up. Or you could call"Randy's Ringand Pinion" and talk to a tech.
http://www.ringpinion.com/
I am sure they will sell you the correct parts you need too.

 

Not to sound noobish but what and where is the RPO located?

Ok, according to
GM 8.5" rearend -RingPinion.com

Does that mean MY R&P is compatible with all those as long as it is the same gear ratio?

 

The codes are located on a sticker in the glove box. It has a bunch of alpha-numeric codes on it. GU6 would be a 3.42 R&P.

 

If you pull the diff cover you should be able to see a stamping on the back end of the pinion gear (eg. 13/41) that tells you the # of teeth on the ring and pinion. If the #'s match yours, then Swartlkk has a good idea. I don't recommend trying to replace the ring and pinion unless you have the specialty tools required and the knowledge and skill to set it up...Bearing preload, backlash etc... for a proper gear pattern.
Just a suggestion based on personal experience.