What is the differential fluid service (rear axle oil service) all about?
The differential is a special gear box located between the drive wheels of your vehicle. It allows the drive wheels to turn at different speeds, as they must when turning a corner. Over time, high operating temperatures can cause the lubricating fluid in the differential to break down, developing a gummy texture that doesn't properly lubricate the gears. Replacing the fluid can help you avoid premature wear on the gears in the differential, and can even help reduce wear on drive-wheel tires.
Keep in mind:
Some vehicles do not have a drain plug. In these vehicles, the differential cover must be removed to drain the fluid. A new gasket is installed and the proper amount of oil is then added.
How it's done:
- Check the fluid level
- Drain and fill the fluid
- Add the correct amount and specification of oil
- Test drive vehicle and check for leaks
You should follow the manufacturer’s guidelines for when to change the differential fluid. Usually this is anywhere between every 15,000 and every 50,000 miles. However, all of the fluids in your vehicle should be checked during regular maintenance services.
What is a common symptom indicating you need a differential fluid service (rear axle oil service)?
- Car is louder than normal
How important is this service?
When you turn your vehicle one way or the other, the wheels on one side of the car need to move at a different rate than the wheels on the other side of the car. The differential is a special gearbox that allows your wheels to do exactly that. It is located between the drive wheels, and helps the wheels turn at rates independent of one another. Like most parts of your car, the differential needs fluid to act as lubrication. When this fluid isn’t properly serviced, it can become contaminated. Contaminated differential fluid doesn’t work very well as a lubricant, and so your differential won’t be properly lubricated. This puts extra stress on the differential and wheels.