Help! Rearend Question

[TheJerryRigger]

I know my 2000 GMC Sierra 1500 Z71 4x4 with a 5.3L has 3:73 gears in the back. My rearend has been makin noise for quite some time now. I didnt think I was keeping the truck long, but turns out I am. It's gotten so worse that I'm scared to drive it to work and back. I am going to autozone tonight to buy a new pinion bearing and pinion seal to see if that will fix it (im hoping its not the gears themselves).

 

How do you tell the size you need? 8.5/8.63" or 9.5"? I would assume its on a tag somewhere?

 

Does anyone have a complete rearend they are trying sell? let me know. GT4 3:73 rearend.

[J-man67]

You have the 8.5/8.6. Not sure if its listed anywhere, but count the bolts on the rear diff cover. 10 bolts = 8.5/8.6 and 14 bolts (Vmax, HD trucks, and some others) = 9.5"

 

Also, where are you located? I just got an email from a supply yard saying they may have the 14 bolt I have been looking for. I will sell you my rear cheap.

[Willshire]

Pinion bearing may do it, as long as the pinion isn't damaged. Could be inner axle bearings too.