[grivera]

I have an early second gen TA rear in my 69 Bird and having it beefed up and have all the parts except the axles. Are the second gen Camaro axles the same length? I ask cause Summit Racing lists the Moser A103003-1 (single axle) as compatible with second gen Firebird

https://www.summitracing.com/parts/msr-a103003-1

But the pair A103003 is listed as not compatible: https://www.summitracing.com/parts/msr-a103003

The specs for both listings are otherwise the same.

The Moser website lists everything by Chevy so not much help there...

[ErikW]

Yes. They should work.

[grivera]

So the second gen Camaros and Firebirds have same length axles?

[Formulabruce]

This a 1970 12 Bolt? I ask because the 71 -81 .. 10 bolt 8.5 does NOT have 30 spline axles and you would need a 30 spline carrier.

[grivera]

I know - I am upgrading mine-

Eaton Trutrac 30 spline and 30 spline axles

Do the second Gen Camaros and Firebirds 8.5 10 bolt rears have same length axles?

[Formulajones]

Originally Posted by grivera

I know - I am upgrading mine-

Eaton Trutrac 30 spline and 30 spline axles

Do the second Gen Camaros and Firebirds 8.5 10 bolt rears have same length axles?

Yes the camaros are the same length as the firebirds. 1st gens between the two and 2nd gens between the two.

Also the 68-72 A bodies are the same length as the 2nd gen Firebird and camaro.

[grivera]

Thanks Larry

[Formulajones]

...............

[Skip Fix]

Yes same length 30 1/8". But getting the 30 splines be sure they are for a 10 bolt as 30 spline 12 bolts the C clip "button" is thicker.

[ID67goat]

A few years back I had ordered axles for my 70 firebird thinking that they are all the same length, but the new axles were longer than the factory originals.

I think it was 29.875 vs 30.125. Do you know why this would be this way?

[grivera]

Originally Posted by Skip Fix

Yes same length 30 1/8". But getting the 30 splines be sure they are for a 10 bolt as 30 spline 12 bolts the C clip "button" is thicker.

Yep - the links I posted in post 1 are for 8.5 10 bolt - length is listed as 30.063 in. Which is 30 1/16”

http://forums.maxperformanceinc.com/...86&postcount=1

[ErikW]

Sorry, guess I should have said yes, they are the same length. How does that rear work out for you under the first gen body? Do you use like a 5" backspace rim?

[grivera]

Originally Posted by ErikW

Sorry, guess I should have said yes, they are the same length. How does that rear work out for you under the first gen body? Do you use like a 5" backspace rim?

Factory 15x7” Rally II with 4 3/8” BS. My street tires are 245 60s - going wider will require more BS.

Pics below with 15x7” wheels and 235 60 MT ET Streets DRs (section width 9.4”)

[HWYSTR455]

This is a quote from 'Monzaz' :

“Pontiac firebird axles are 29 ¾” – 29 7/8” same as the 68-72 GTO as I stated the firebird 67-69 rear is the same overall width as the 70-81 firebird BUT the spring perch on the 67-69 is 42 7/16” center to center and the 70-81 firebird is 45 3/8” center to center. Remember with a BOLT IN AXLE the axle shaft is about a ¼” away from the center pin they do not touch the center cross pin as a c-clip rear does. So we really do not measure the full length of the axle like we do with bolt in axles. GM has a 2.75 drum brake offset and the firebird 67-69 housing is 55.25 from axle end flange to axle end flange…then add the 2.75 x 2 and you get your overall width. This comes to roughly 60.75 overall, this is the reason for the Pontiac extra .25 backspacing on the rims. So they sit under the car with the little skinny tires they used back in the day.”
The way he measures c-clip rear ends is he adds axle length x2 plus the width of the center pin and gets outside to outside (overall) width of the rear end. With this measurement you know exactly what you are dealing with because you are measuring through the center of the rear end and that will not change.
Here are some common measurements that might help with determining what will work for your application:
8.5 (10 bolt): Center cross pin width 0.795” ; axle 30.062 Total width= 60.919”
8.2 (BOP 10 bolt): Center cross pin width 0.733”; axle 30.00 Total width= 61.233
8.875 (12 bolt): Center cross pin width 0.800”; axle 29.75” to 29.875 Total width= 60.3” to 60.55”

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[grivera]

Thanks Mike - the weird thing is my factory 8.2 is narrower than the second gen 8.5 that replaced it. Based on what's described above it should be the other way around.

[Schurkey]

Originally Posted by Skip Fix

Yes same length 30 1/8". But getting the 30 splines be sure they are for a 10 bolt as 30 spline 12 bolts the C clip "button" is thicker.

Thanks for that.

Years ago, I read about guys shortening the "button" with an angle-grinder (!!!) to make the axle shafts fit. I always wondered what was going on with that. I guess they ordered--or received--the wrong axle shafts.

[grivera]

My axles arrived today and I found this blemish on one of them - Will it cause an issues with areal or bearing? I’m inclined to think it doesn’t. Thoughts?

[Schurkey]

It's not on the seal surface, or the bearing surface.

Ugly, but inconsequential.

[HWYSTR455]

Originally Posted by grivera

Thanks Mike - the weird thing is my factory 8.2 is narrower than the second gen 8.5 that replaced it. Based on what's described above it should be the other way around.

The measurement spoke of is from axle flange to axle flange, with the 8.2 bolt in axles, with the axles in the housing.

.

[grivera]

Originally Posted by HWYSTR455

The measurement spoke of is from axle flange to axle flange, with the 8.2 bolt in axles, with the axles in the housing.

.

With drums and wheels on in car the 8.5 in my car is effectively wider than the 8.2 it replaced.