I'm buying some 4.10's and a tru-trac but I don't know squat about rearends.

I haven't looked yet but I think i have a 10bolt. I'm looking online and I see gears for the following:
GM 8.2 - 10bolt
GM 7.5 - 10bolt
GM 8.5/8.6 - 10bolt

I'm assuming the first numbers are the axle diameter? How do I determine which I have?

Edit: Also, isn't there a 28 and 30 spline count on the 10 bolts? how can I determine that without tearing into it.

 

I'm pretty dang sure you have the 8.5" 10 bolt rearend. But im not 100%

 

That's what I'm thinkin too, but I don't wana be wrong.

 

913A481 Locker part #

 

you should have 8.6 30 spline

 

I've got a yukon 8.6 master rebuild kit all I used was a little of the paste and a small shim. I'll let you have it for 115 shipped. you'll need it for the gear install.

 

that's a lot of shipping for an item your letting me HAVE.
Wait until I get everything else. I'll talk to my installer and see what he's got, If I need it I'll holler at ya to see if you still have it.

 

It's a 10 bolt. now is there any sure fire way to determine the spline count and axle diameter?
aside from the obvious.

 

if it's an 03 and up and you have 10 bolts on your differential cover. then it's a 8.625 30 spline.

 

Just ordered 4.10's Truetrac and Master kit package for $584.99.