What are the widths of various GM rearends?

[Richz68]

I am trying to find a GM 8.5" 10 bolt rearend for my '68 Camaro. I will be running a set of C5 wheels so ideally I would like to get a 8.5" that is 3.5" wider than the stock 1st gen F-Body rearend to properly match the positive offset of these wheels.

Does anybody have any ideas how wide the various 8.5" rearends are?

For more info on the 8.5" use this link: 8.5" 10 bolt tech (http://chevyhiperformance.com/techarticles/48518/index.html)


:icon996:

[Kenova]

I don't have any measurements for you, but you may want to check the width of the rear ends in early '90s full size vans. They have a 5 on 5 bolt pattern (not good) but have huge drum brakes (which you probably don't need). I'm quite certain they use a 30 spline axle also.
Ken

If anyone happens to come across the width for third and fourth gen F bodies, I'd really appreciate you letting me know.
Thanks

[airrj1]

Rich,

I have Z06 rims for my Chevelle. My wheel adapters are 2.125" each in the rear. I found a 9" Ford out of a half ton pickup is exactly 4.250" longer than the stock Chevelle. So I am hoping some day this will easily replace my 8.2" and wheel adapters.

I don't know any dimensions off hand, but I found most of the dimensions by searching over at Team Chevelle and Team Camaro.

I like your idea.

[JRODHOTROD]

try this, might help
http://www.chevytrucks.org/tech/ifs&rearend.htm
scroll all the way down

[Richz68]

I discovered that '91-96 Caprice/Impala/Roadmaster 8.5" 10 bolt differential assemblys should be the perfect width for me to use my C5 wheels. The stock 1st gen rear end measures 60 1/4" between the outermost surfaces on drums. The Caprice/Impala/Roadmaster differentials supposedly measure at 63", which will be just about perfect. These rearends also have heavier 30 splined axles which are the same as the 12 bolts and some even have rear disc brakes with PBR calipers! :bananna2: The down side is that the coil spring perches need to be removed and a set of leaf spring perches need to be alligned and welded to the housing. The axles also have 5x5" bolt patern and the center hub diameter is too large for wheels that use 5x4.75" bolt pattern. The center housing also extends about one inch further forward towards the front of the car as compared to the stock housing so your driveshaft needs to be shortened.

I found a posi from a '95 Impala SS from a guy at work that has already been redrilled to the 5X4.75" pattern and center hub was cut down to allow smaller wheel hubs; it even has rear disc brakes! I will take my wheels with me tomorrow to measure them on the Impala diff to determine if it is a good fit.


I will keep you guys posted!

[airrj1]

Very cool. Good idea on the B-body I didn't think about them. Don't forget to give us some :pics2:

[Richz68]

Your wish is my command....I got the Impala SS diff home and mocked the wheels up, but I will still have to use small spacers, but at least they will not need to be as thick to space the wheels correctly.



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