I'm dead set on rebuilding the rear in my 1LE to beef it up a little and don't want to swap to a completely different rear. Can anyone tell me all the specs on the 9 bolt? Like overall dimensions, # axle splines, every little detail?

I'm trying to source the parts now but I want to make sure that I know exactly what I'm looking for first so I don't buy the wrong peices.

I want to get a new posi, moser axles, ring & pinion install kit, new 3:42's, axle bearings/seals, TA girdle & stud kit, etc.

I'm looking at what summit has but there are quite a few options so I could use help figuring out what's what.

 

Not sure if I understand the goal. Do you want to build a "strong" 9 bolt "Aussie" rear end as came in 1LE or do you just want a 9 bolt case with all new non-stock insides?

Providing the specs on how to build a stock diff won't be of much help if you are going with all new non-stock innards.

 

I want to use all aftermarket internals for my stock 9 bolt carrier that's in the car. I was just referring to it as the aussie unit because I'm not sure what the differences are and I know that's what's in it stock.

My thoughts would be Eaton posi unit, moser axles, the TA girdle & stud kit, new 3:42's, etc. So yes, just keep the factory housing and put beefier internals in it. It's a factory rear disc setup obviously, if that makes a difference.

 

OK then I wouldn't spend time collecting information on the details of the parts you are not using. Not sure about who makes what aftermarket parts for the 9 bolt as it was really a light weight rear end not intended for high HP usage. That said have you done a search here to see what parts others have used.

I found info with a simple Google "camaro 9 bolt rear"

 

https://www.thirdgen.org/forums/faq-...now-about.html

JamesC

 

If you really, truthfully have a 9 bolt rear under your 92 1LE, then someone has changed the rearend. The 9 bolt was phased out completely in the f-bodies by 1990. All of that stuff you've been looking at on Summit's website is for a 10 bolt rear, guaranteed. Count the bolts again on your rearend cover and make sure what rear you've got. Another easy way to identify the 9 bolt rear is it has a rubber fill plug in the back cover. If you do end up having a 10 bolt under there, here's your specs. 7.5/7.625" carrier, 28 spline axles, pinion shaft diameter-1.438", pinion spline count-27. If you have a 9 bolt, forget about buying a new posi unit or new 3.42 ratio gears as they're simply not available anywhere. Here's a great site for rearend parts and info: http://www.ringpinion.com/

 

9 bolts, rubber plug. Just changed the fluid 2 weeks ago so I'm sure.

Where are you getting the info that my car shouldn't have a 9 bolt? I'm not saying you're wrong but I thought the rear in the car was SUPPOSED to be a 9 bolt. I've seen more than a few 1LE's with the same option. I was under the impression that the factory disc rear in 3rd gens was a 9 bolt. The RPO never changes on the 1LE cars to suggest different.

And I spoke to both past owners, car hasn't been touched.

 

IIRC, 89 was supposed to be the last year for the 9-bolt (but, hey, this is GM were talking about). I'd suggest there were far more 10-bolts in thirdgens than 9-bolts.

JamesC

 

Hello nighthawk355x!!

Is one of the both past owners the original owner from day one, or did the first owner get a "dealer demo" with junkyard parts like I did???



Short story:

I bought a "dealer demo" 1987 IROC-Z that had 19952 kms on the odometer, and was 14 months old when I got it, and it was owned by two "stealerships" before me!! One of the two "stealerships" replaced the complete rear end with the correct type, but wrong axle ratio from what was on the car when originally built!!

SPID Reads:
RPO J65, G80, GM3 = 4 wheel disc brakes, posi, 3.45 ratio B-W 9 bolt!!

Actually on the car:
RPO J65, G80, GW6 = 4 wheel disc brakes, posi, 3.27 ratio B-W 9 bolt!!

My car is a 5 speed, I'm supposed to have the 3.45, not the 3.27!!

The 3.27 is for the 350 with auto!!

 

I have to agree with the other guys, there's definitely nothing set in stone when it comes to how GM built each particular car. It's totally possible that they could've had an extra 9 bolt sitting on the rack at the assembly plant and decided to put it in your car so they could get rid of it. Your car being a 1LE makes it even more possible since the 9 bolt was considered the "heavy duty" rear. As a general rule of thumb though, it's just like JamesC said, the 9 bolt was phased out sometime in 89. After they were supposedly phased out that year, all remaining 3rd gens from 89-92 got the 10 bolt rear, whether it was disc or drum. In fact, the 89 9 bolt disc rear is highly sought after because it was the only year that the 9 bolts got the much improved PBR aluminum calipers. All 88 and older rears, whether 9 or 10 bolt, got the problematic cast iron calipers. So yeah, don't worry, I'm not calling on your claim, it just seems really strange for a 92 to have come with a 9 bolt! It's even possible that the car might've had a rearend problem while still under warranty and had it replaced at a dealership while the car was still pretty new.

 

Oh I know, and I'm not trying to argue that at all. I was just legitimately curious about the info on the rears. I had been trying to look into it but couldn't find squat. Originally I had figured it has the 9 bolt because they just kept them in the 1LE cars, but I never assumed that to be 100% fact because I don't know enough about that.

And weirder yet...I'm almost 100% positive the rear in my car DOES INDEED have the PBR calipers. I have to check for sure but I could swear it does. This is easily the biggest mystery of a car I've ever owned...it's got some non-factory parts in it and some really oddball peices that were installed when it was almost new.

 

Actually, it having the pbr's isn't strange at all since ALL f-bodies from 89 on up got them whenever they were optioned with 4 wheel disc brakes. But yeah, I'm always hearing stories from guys who end up with oddball stuff on untouched cars. With the General anything's possible!