[firebirdmi]

I'm replacing my rear axles on a 8.5 posi c-clip and found the axle length to be closer to 29.625 than 29.5. I would like to get the Moser brand but they only have 29.5 length without going custom length and there is some play (more than what is needed to remove c-clips). Do you think the rear can accommodate the smaller length? Thanks

[Skip Fix]

What year 8.5 C clips? late 70s are actually 30 1 1/6 to 30 1/8 and Moser has them in 28 and 30 spline. Same length as 12 bolts but the 10 bolt has a shorter "button" on the cross shaft side of the C clip.

http://www.moserengineering.com/axle...nte-carlo.html

Too much free play can be because the clutch pack in the posi is worn.

[firebirdmi]

Rear was from a mid 70's Nova and fits in my 68 firebird. The actual measurement from the outside wheel flange to the end of axle was about 29.6" ( there is some measurement uncertainty due to). It definitely seemed closer to 29.6 than 29.5. In addition to the original question how much play in/out should the axle have with a good condition posi?

[Skip Fix]

Explains why they are shorter.

Here you go standard C clips not custom

http://www.moserengineering.com/axle...8-76-nova.html

Free play can be because axle button or cross shaft has worn, or more generally clutch packs have worn. There are a few thicker C clips available also. Downside there is only one guy repopoing clutches and the go for about $200, or jump to a new 30 spline Eaton and 30 spline axles if you need new axles.

I want to think about a 0.010 free play max. I think Tom's Differentials has a You tube on setting up GM posis and discusses setting up the free play.

[firebirdmi]

Thanks for the help Skip.