What happens inside a differential rebuild?

Summary:

Jaden explains that most differential rebuilds come down to bearings. A standard rebuild consists of all new bearings and seals. Beyond that baseline, the scope of the job is determined by inspection once the unit is open. At that point the shop can determine whether the differential also needs a new ring and pinion, a new carrier, or new axles. He repeats the central point twice, that most differentials are a bearing job, and that the rest of the parts list depends on what the internals actually look like once the shop is inside. His answer sets a realistic expectation for customers: the differential rebuild starts as a bearing and seal job, and any additional hard parts are identified during teardown rather than assumed at the estimate stage.

Answer:

So differential rebuild, most of the time, is bearings again. So a rebuild would be all new bearings and seals. Once we get in there, then we can see if it takes a new ring and pinion or a new carrier, or new axles. Most differentials are a bearing job, and then again, we see what it looks like once we're in there with their stuff. That's really how these go. The bearings and the seals are coming out no matter what, because that's what fails most of the time and that's what you're in there for. Everything past that is determined by inspection. We get it apart, we look at the ring and pinion, we look at the carrier, we look at the axles, and then we know whether this is a straightforward bearing job or whether it needs hard parts. Until it's open, you're guessing, and I'd rather look at it and tell the customer what it actually needs.