I'm helping a neighbor kid build a mild hot rod, and I'm trying to save him some money. I know the stock 10 bolt is as weak as they come, but he can't afford, an aftermarket rear end, so I was thinking of throwing an aftermarket differential, and gears in his stock 10 bolt. I was wondering if I could save him some more money by reusing his stock axels. Would they hold up to 550# tq with slicks, or even on street tires?

 

They will probably break after the gears.

 

The 82 to 88ish cars had 26 spline axles, and later 28 spline, a bit stronger...
On street tires, it may live a long time, but 550 tq, save up for something that can handle it... I beefed up my 10 bolt, but don't have that much power and always will be street tires...