Solid Pinion Bearing Spacers vs Crush Sleeves
Both set the pinion bearing preload, but they do it in very different ways. Here is why we use solid spacers on most of our rebuilds.
A crush sleeve is a thin steel collar that collapses as the pinion nut is torqued up, setting the preload on the pinion bearings. It is cheap and quick for the factory, but it only works once and it is easy to overshoot.
Why we prefer solid spacers
A solid spacer with shims is set once and stays set. If the pinion nut ever needs to come off, the preload is still right when it goes back on. It also takes the guesswork out of high torque applications where a crush sleeve can keep collapsing.
When a crush sleeve is fine
For a standard road car with a factory gearset, a new crush sleeve fitted properly will do the job. We just make sure it is done with a torque wrench and a dial gauge, not an impact gun.
