According to the stamp on the axle housing, my '68 has a 2.73 ratio rear end. I believe that automatically makes it a a Series II carrier in the differential.

In order for me to put in a larger gear ratio i.e. 3.42 or 3.55 I will first need to replace my existing carrier with a Series III. Can I actually install a Series III carrier in my existing rear axle housing even though it was originally designed/built to hold a Series II?

If I am replacing the carrier can I and should I install a Posi? Will I need to change the axle if I switch carriers?

Last question: where do I go to get a new carrier for my car?

Thanks,

Vic

 

is the rear a 10 bolt or 12 bolt? try going to Custom Axles and Rear Ends by Dutchman Motorsports | Brake kits | Housings | Differential Components | Ford 9" | Quick Change | Dana 60 . these guys are local to me but ship anywhere and can do anything relating to axels and housings and could answer any question on yor situation and what you want to do. it dosent show stuff on gm axels but i know they work on them because my grandfather has used them over the past 30 years

 

Thanks camaroboy. It is 10 bolts on the rear pan. (Is that what makes it a "10 bolt" rear end? I was under the impression that "10 bolts" refers to the bolts that hold on the ring gear.)

One more question, about splines. Based on what I've read, the axle spline count should be 28. Will the yolk spline count for the pinion also be 28?


I will definitely follow up with Dutchman.

Thanks again.

Vic

 

You will need a III series carrier. I recommend installing a posi. Auburn makes about the best unit around in my opinion. I believe they still offer a 28 spline unit, somebody tried to tell me they discontinued it , but, I still see it offered. It will fit the housing and work with the axles. (Don't worry about the pinion spline count. A 10 bolt is a 10 bolt is a 10 bolt, The gears in your '68 will fit in the new AAM 10 bolt built now. They changed everything else, but, the gears are the same).

"Sorry, the last few sentences are inaccurate, disregard"

 

All 10 bolts are NOT alike, so a 10 bolt could be different splines on the axle end depending on whether it's a 8.5", 8.2", 7.7", etc..... I would guess your first Gen Camaro is a 8.2", but you need to figure that out prior to ordering anything for it.
You can change the gear ration to a 3 or 4 series gear without changing carriers, if you get the correct ring gear spacer. My Austin gasser has a weird Canadian 10 bolt in it and I was unable to find the correct 3 series carrier to go from 2.73 to 3.73, so we just put the spacer in and it's working great.
If you go to a posi, then you definitely will have to change carriers, so no reason not to go to a 3 series posi carrier. To determine which axle spline you have simply pull the axles and count them.
Dutchman's is great on most axles. They did the axles in my '71 Camaro and my '46 Austin. No problems with either, but I have friends who had them build axles for their race cars and blew them out the first run, and those were 35 spline 9" Ford axles! I'm not 100% sold on their products for high performance race use.

 

yeah the cover is what determines a 10 or 12 bolt. oll of the perfornce chevys got the 12 bolt so all ss camaros got one. to be able to quickly identify what rear end is to look at the bottom of the cover . it there is 1 bolt in the middle on the very bottom then it is a 10 bolt. if there are 2 bolts that are spaced apart and then there are no bolts in the middle then its a 12 bolt. here are some pics of the covers.

a 10 bolt


a 12 bolt

 

Good call out, you got me. I got my head completely stuck in the 8.5 inch world. I have rebuilt so dam many that I forgot the others even existed, my fault, sorry. The '68 should be an 8.2 As far as the 8.5 chevy goes, the ring and pinion are the same to '98. The truck carrier changes in late '98, so, '99 up has a larger carrier bearings. You can recommend gear spacers if you want, but moving the ring gear off the carrier, weakens the assembly and allows for more movement. This can cause other issues. I can remember three jobs where a spacer was used, all had the same failure. The last one i did was a 12 bolt which took out the original housing.

 

No, I wouldn't go a spacer for a hi performance situation, but sometimes there isn't an option. I certainly wouldn't have done it myself, but considering the oddball carrier my Canadian GM rear has, there was no other option, plus the 40" wide axle fit, and saved a ton of money over just starting from scratch and building a new one for my project. If the rearend is a common one, then a carrier change is much preferred. I was simply stating that a carrier change is not the only option.

 

Thanks for all the answers and input, folks.

Very helpful.

Vic

 

to be honest if your gonna replace the carrier,gears,axles etc... you would be money ahead to find a quality rebuilt 12 bolt and swap the whole thing as it will be close to the same in cost!!!
talk to this guy (tlowe) on www.teamchevelle he builds rears for a hobbie(side cash) and is very good and ships them all over!! he built the 12 bolt in my 71 chevelle and even gave me a 1 yr warranty and it has been flawless for past 3 yrs!!!
tell him what you want and what you have to spend.