It used to be that when part of your car failed, like the starter or alternator, instead of replacing it, you would get it rebuilt. Nowadays, very few parts ever get rebuilt because of the convenience and now lower cost of simply replacing the entire part. The parts that were replaced get sent back as a “core” to get rebuilt and sold as a remanufactured part. Because of this, it’s rare that you get to take things apart to see what failed or just how they work, because it has to be intact to get the core charge refund.

Once in a while, a part doesn’t have a core charge, so it doesn’t have to get returned. That was the case with the rear differential I recently replaced on a Honda CR-V. I got the chance to take it apart and see what was going on inside it.

Behind the rear cover is just your typical open differential set, just like any front engine rear drive vehicle. One difference between this and a typical rear axle’s differential is that the case itself holds the gear set in, instead of separate bearing caps.

Under the front cover is where things are different from a regular rear differential. The input shaft first goes into a clutch pack. When the front and rear wheels begin the spin at different speeds, the clutch automatically activates, sending power to the rear wheels. Behind the clutch pack is the fluid pump that provides the pressure for the clutch.

New blog posts every Monday and Thursday, plus pictures throughout the week on Facebook, Twitter, and Instagram!

Mechanical Malarkey T-shirts, hats, and stickers are available to order!

-Dan