Mid 60s C-Body 8.75 axles... cant shorten them?!?

67GTConvert said

Supposedly the case hardening extends down the axle into where the new splines are cut so there's still some strength there but cutting new splines into a case hardened shell won't be as good as the factory roll forged splines.
As a previous poster stated,they probably won't stand up to drag race starts with slicks but are likely fine for mild street cars on street tires.Personally I can't picture my 273 2bbl stripping splines off any kind of rearend never mind an 8 3/4.

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Typical axle case hardening is .150 thick and 8 3/4 axle splines are about .050 deep, so the resplining should be in the hardened zone. But as 67GTConvert says, the factory roll forged splines are better. Supposedly Chrysler axles are made of 4140 steel with a typical yield strength of 106,000 psi. Like oldkimmer was saying, if you get racing axles, some go up to 210,000 psi yield strength. There are also disadvantages to running racing axles on the street. I'll leave that to someone else. I run on the street and am going to try resplined axles. Time will tell.