A car's differential is constantly under stress, so it's no surprise that eventually its gears will wear out. And once those gears give out, the differential has to be rebuilt to prevent additional damage to your vehicle. Differential rebuild kits are meant for such a purpose, containing all the necessary components to restore a car's differential back into working order.
Choosing the right kit
While all rebuild kits are meant to get your car's differential up and running again, they are not designed equally. Some kits, for example, cater to the budget-conscious while others focus more on performance than on price. And finding the most suitable kit for your needs is essential to ensuring that you'll get what you need without overspending.
Different manufacturers offer different rebuild kit packages, although they can roughly be categorized into the following:
- Basic differential rebuild kit. This kit contains the essential parts needed to rebuild the differential, including the pinion and carrier bearings, pinion seal and nut, crush sleeve and o-rings where applicable.
- Pinion differential rebuild kit. Designed for budget rebuilding where the pinion rings are the only parts to be replaced or for low mileage ring and pinion gear ration changes. Contains the pinion bearings, pinion seal and shims, crush sleeve or depth shims, o-ring and gear marking compound and brush.
- Mini differential rebuild kit. Similar to the pinion differential rebuild kit except that it does not contain the bearings. It also usually comes with Loctite or a similar adhesive, carrier or super shims and an instruction manual.
- Master differential rebuild kit. The Master rebuild kit contains everything needed to rebuild the car differential. The kit contains the pinion and carrier bearings, pinion seal, pinion shims, pinion nut, crush sleeve or depth shims, o-rings, carrier or super shims, slingers and baffle and, in some applications, ring gear bolts. Most master kits will also come pre-packed with Loctite, cover gasket or silicone and installation manual. Because it contains all the components for the differential, this kit is one of the most expensive.
Heavy duty vs. light duty
When shopping for differential rebuild kits you'll probably encounter
heavy rebuild kits. Basically, the difference between these two kits is that the light duty kit is meant for consumer vehicles, such as sedans and SUVs for example, while the heavy duty kit is meant for heavy trucks. So unless the differential you want rebuilt is in a semi that's meant to lug a trailer on Interstate, a light duty differential kit is the definite choice for you.