G80
AXLE POSITRACTION, LIMITED SLIP

G92
AXLE REAR RATIO, PERFORMANCE

GU6
AXLE REAR, 3.42 RATIO



can anyone tell me if this is a 9 or 10 bolt rear end? i believe its off iether a 86 or 87 iroc. and if its a 10bolt, how well can it hold up to my car with whats listed in the sig?

 

If its a 3:42 then its a 10-bolt.

 

will this disc brake ten bolt be a worthy swap to replace my 2.77 disc 9 bolt? can i retain my disc rotors and calipers if i swith to the 10bolt?

 

In my opinion, NO to the first question and No to the second one also: Reason the 9-bolt is a stronger rear with better brakes and don't belive everything about the 2:77 gears being a poor ratio..

 

Any 9 bolt has the same brakes that were available on a 10 bolt of the same year.

 

If you would read the first of his posts, he has a 1989 2:77 9-bolt that came with the 11.655 rotors and Alum, PBR calipers. Not the same as the early 10-bolt 10.5 rotor dia. The BIG reason he wants to swap brakes which he can not do.

 

i wouldnt be able to swap the discs from my 9bolt to the 10bolt?

 

You could easily put the PBRs on the 10 bolt with new backing plates.

 

ok then, i think im gonna get this 10bolt. where can i pick up backing plates. not familiar with this?

 

The last I checked they were still available from GM, that was a while ago though. 10136853 for the left side, 10136854 for the right.

 

Good luck trying to find them,,,,,,,,,,,,,,

 

You're thinking of 9 bolt backing plates. I just checked with GM Parts Direct, both of the 10 bolt backing plates are still available.

 

ok question, since i just got home from work, what do the backing plates do exactly?

 

The backing plates bolt onto the axle flange and the caliper brackets are mounted to them.

 

hey i was thinking, can i take the backing plates off my current 9bolt and just bolt them to my new 10bolt axle?

 

No, they're the only part that's different between the 10 bolt and 9 bolt brakes. GMPartsDirect has each plate for something like $11, so it's not like you'd go broke on them or anything.

 

ok so i need these backing plates that bolt to my 10bolt, so my calipers from my 9bolt can bolt to them? my 9bolt backing plates wont bolt to my 10bolt?

sorry if the question sounds stupid, making sure we are on the right page.

 

Right, the flanges on the ends of the axle tubes have different bolt patterns on the 9 bolt and the 10 bolt. The bolt pattern on the backing plates has to agree with the pattern on the axle flanges.

The reason the PBR 9 bolt backing plates are so rare is because they were only available for a short time before the 9 bolt was discontinued. 10 bolt backing plates were used much longer and are more common than dirt.

 

thanks. Now I looked at my current 10bolt axle more closely, looks like I Have to pull the half shaft axle out in order to get the backing flange off? Is it hard to pop those out? or wait.. let me say it in a positive way.. how easy is it to remove these, and reinstall them once new backing plates are on?

 

TTT