Got questions?

We’ve got the answers—the Summit Racing tech department tackles your automotive-related conundrums. This week, we’re looking at posi- and non-positraction rear-end setups.

T.J. • Columbia, SC

Q: I’d like to know how to identify positive or non-positive traction configuration on Ford and Chevy rear-ends. Is there a quick way to tell? Can you recommend any other resources on the subject?

A: If the rear-end is still installed on your vehicle, then start by jacking up one rear tire. Next, try turning the tire that’s off the ground. If it doesn’t turn, then you have a positive traction configuration. If the rear-end is off your vehicle, you can still perform this test. Just put a bar or wrench through the wheel studs so one side is locked to the ground. Then, turn the opposite side to test it.

For extensive information about this topic, add High-Performance Differentials, Axles & Drivelines to your gearhead library. The 144-page book is jam packed with information on how to identify your setup, match components for rear-end longevity, and it even has handy rebuild reference material.