Common questions

How tight should pinion nut be?


How tight should pinion nut be?

Be careful a quarter turn past optimum is way too tight. You only want 12-20 in. lbs of torque on the free spinning pinion. If you go too tight, the only thing to do is take it apart and crush a new sleeve.

How do you check pinion depth?

You must calculate the pinion depth on most OEM gear sets. You can do this by measuring the thickness of the pinion gear head and subtracting that measurement from the factory mounting distance measurement. The end result is your pinion depth.

How do you adjust the pinion gear depth?

Each gear set is pre-run and marked on the pinion face with its proper depth setting called the “Checking Distance”. This dimension is from the face of the pinion to the axle centerline. A setting tool must be used to measure the checking distance. Pinion depth is adjusted by adding or subtracting shim thickness.

What happens if you have too much backlash in differential?

This distance is application-specific* and is critically important on all differentials because insufficient backlash causes the gears to bind, while excessive backlash causes excessive mechanical wear. Note that both inadequate and excessive backlash can cause varying mechanical noises.

What happens if you pre load a differential pinion?

A Pinion with too much pre-load will overheat and destroy the pinion bearings requiring a complete differential teardown and rebuild. My objective was not to reset the Pinion pre-load, but to increase the Pinion pre-load incrementally until Pinion movement was eliminated.

What does backlash mean on a pinion differential?

Backlash is how far the ring gear sits from the pinion gear once installed in the differential. You’ll find the backlash specification for your ring gear in the documentation with your gear set.

How does the pinion gear depth affect the bearing?

The pinion gear depth refers to the distance the pinion gear extends into the carrier. Pinion depth affects where the pinion gear teeth meshes with the ring gear teeth. Pinion gear depth is commonly adjusted by varying shim thickness on the pinion gear and bearing assembly.

What causes a differential pinion to move when torque is applied?

Pinion pre-load is lost gradually over the life of the differential as the bearings and or race wears with use. This wear can cause enough pre-load to be lost that the pinion will actually move when torque is applied or removed to the pinion via the driveshaft under engine acceleration or deceleration.