Grand National, Differentials

GM’s 10-bolt rear axle has been around since the 1960s, here’s how to determine if your junkyard find is worth taking home

A short article explaining the main differences between open and limited slip differentials.

A brief overview of the steps Speedway Motors takes to ensure you get a quality differential.

Decode, ID, and upgrade your GM 12-bolt rear end. Learn axle specs, gear ratios, and best performance parts upgrades.

Learn about GM alternator identification in our guide. We cover GM 3 wire alternators, 1 wire alternators, and externally regulated so you know what to choose.