Time for a Differential Service on your car?

December 14th, 2018

Let’s talk differentials. If you have a rear-wheel drive vehicle, your differential is on the back axle. With front-wheel drive cars, the differential is up front. All-wheel drive and 4-wheel drive vehicles have three differentials – front, rear and in the middle. So you see, you’ve got a differential (or two or three) and it needs servicing now and then.

What does your vehicle differential do? Well, it compensates for the differences in speed between your outer and inner wheels in a turn. Using the dimensions of a typical car, let’s compare the distance the wheels travel from the start of a turn through to the completion of the turn.

The inside wheel travels about 3.8 metres. How much farther does the outside wheel travel? About 5.7 metres – almost 2 metres more. This means the outer tyre has to rotate 9 times in the same amount of time that the inner tyre has to rotate only 6 times – so the outer tyre needs to spin faster in order to keep up. The differential makes this possible.

The gears in the differential are cooled and lubricated by differential fluid. It’s this fluid that needs to be serviced. Tiny bits of the gears can wear off over time and become suspended in the differential fluid. The dirtier the fluid, the faster the gears wear out.

Your Oil Changers technician drains the old fluid out and replaces it with the correct fresh fluid. Some differentials also need a special additive that is put in at this time.

So when should you have your vehicle differential serviced? Intervals vary from vehicle to vehicle – and may be as short as 24,000 km. Check your vehicle owner’s manual or ask us next time you come in for a service. If you frequently drive with heavy loads, tow a trailer or drive in hot conditions, you probably need to change differential fluid more often. Servicing your differential on schedule at Oil Changers can save a pricey replacement down the road.

Give us a call.

Oil Changers New Zealand