How do I know if my 12-bolt is posi?

How do I know if my 12-bolt is posi?

If you see springs in the window of the carrier, either coil springs like this or an S-shaped spring, it’s a Posi unit.

Are all GM 12-bolt rear ends the same?

They are not interchangeable. That doesn’t mean the truck rearend is not capable of receiving performance upgrades. To the contrary, aftermarket 30-spline differentials and axles are available. GM car and truck 12-bolt rearends are easily distinguishable by the cover shape.

How do you identify a 12-bolt GM rear end?

The easiest way to identify a 12-bolt rearend is obviously by the 12 bolts holding the rear cover onto the axle housing. The pinion shaft on passenger-car differentials is 1-5/8-inch in diameter and the cover is oval, measuring 10-15/16-inches wide by 10-5/8-inches tall.

Is limited slip the same as Positraction?

Positraction, or positive-traction rear end, is a brand name for a limited-slip differential (LSD), which helps distribute power to the rear wheels and ensures that they are spinning at the same speed.

What cars came with posi traction?

Positraction was first introduced by GM in 1957 with its 8.875-inch 12-bolt Positraction unit, which was common in Chevrolet passenger cars from 1965 to 1972 and Pontiac countered with their version of the Posi rear end, called the Safe-T-Track in the 1963 Tempest.

What did GM 12-bolt come?

12-Bolts to Glory The GM 12-bolt debuted in 1965 and was mass-produced until 1972.

Is posi traction the same as a locker?

With a locker both wheels will spin at the same speed. With a posi it allows the wheels to turn at differenthe speeds. When turning the inside wheel needs to turn slower than the outside .

What’s better 10 bolt or 12-bolt rear end?

First, the 10-bolt’s pinion shaft diameter is 1.438 (25 splines) while the 12-bolt is 1.625 (30 splines) which makes the 12-bolt 13 percent larger in diameter and therefore stronger.