GU6 Rear Axle?

I looked at my RPO's today on my 85 IROC, and the RPO for the rear axle is GU6. I looked it up and it is 3.42 gears. My question is, does anyone know anything else about this rear end? Like, is it a open or LS, is it a posi? Also, how much power can it handle? Well, I would like to know as much as possible about this rear end. Thanks!

Im pretty sure its a posi, but dont quote me.

GU6 is only a gear ratio code.

I looked at my RPO's today on my 85 IROC, and the RPO for the rear axle is GU6. I looked it up and it is 3.42 gears. My question is, does anyone know anything else about this rear end? Like, is it a open or LS, is it a posi? Also, how much power can it handle? Well, I would like to know as much as possible about this rear end. Thanks!
gu6 just tells what ratio u have. if u also have the code G80, than its a 3:42 posi. i don't think the factory rears can take alot of hp and torque.

What if I don't have G80 or G92 axle codes?

What if I don't have G80 or G92 axle codes?
than u probably have an open 3:42 diff

power isnt what will kill a rear end. Traction will. you can have 800hp and ride on a 10 bolt. Put slicks on that 10 bolt and then it wont have a chance. Your rear should be fine as long as you maintain it properly. It is getting old as its over 20 years old so you bearings are probably worn but if it isnt whining then your good.

you need the number stamped on the rear-end... the right hand axle tube i think..that will tell you all you need to know.. the first three numbers is your axle code
1985
8JA 3.08 OPEN
8JB 3.23 OPEN
8JC 3.42 OPEN
8JD 3.73 OPEN
8JP 3.08 POSI
8JQ 3.23 POSI
8KA 3.42 OPEN
8KB 3.73 OPEN
8KR 3.08 OPEN
8PP 3.08 POSI
8PQ 3.23 POSI
8PR 3.42 POSI
8PS 3.73 POSI
Now you an be lazy and you dont have to look it up!

Now you an be lazy and you dont have to look it up!

LOL, Thanks..... I think..... Actually I have seen those codes on thirdgen.org I think. I just didn't know where to look on the car to compare. Thanks for the information though, it is quite useful.