Oil Changers

Servicing Tips - Drive Train


Time for a Differential Service on your car?

2018-12-14 07:19:03

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
PO Box 16686 Hornby
New Zealand, New Zealand 8441
03 3442374


Drive Train Services for your vehicle

2017-05-14 11:46:03

The drive train in your vehicle includes all the components that transfer power from the transmission to the wheels. Those components differ depending on what type of vehicle you drive, namely, front-wheel drive, rear-wheel drive, all-wheel drive or four-wheel drive. The preventive maintenance your driveshaft needs will also differ by what type of vehicle you drive.

Let's start with front-wheel drive. In this vehicle, the transmission and the differential are combined in one component, known as the transaxle. The transaxle is connected to two half-shafts (axles), which are then connected to the wheels with a constant velocity (or CV) joint, which is protected by an airtight rubber boot.

Oil Changers service for this type of drive line includes servicing the transaxle and inspecting the CV boot. If the boot is damaged, the CV joint will need to be inspected, and the boot will need to be replaced. If you hear a clicking noise in your wheel wells when you turn, you may have a damaged CV joint. A damaged CV joint should be replaced.

Rear-wheel drive vehicles generally have a transmission in the front of the car and the differential in the back. A driveshaft (it looks like a long tube) connects the transmission to the differential. Some vehicles may have a two-piece driveshaft, which are connected to the differential with universal joints or U-joints. Again, the differential is connected to two half-shafts that go out to the wheels.

Oil Changers service on the drive train on a rear-wheel drive vehicle starts with servicing the differential. It will need its fluid drained and replaced regularly. The seals on the axles should also be inspected for wear or leaks. Leaking or damaged seals may mean the axle needs to be serviced as well. Also, U-joints can wear out. If you hear clunking or feel a jolt when you shift into drive or into reverse, it could indicate a driveline problem.

All-wheel drive vehicles provide power from the transmission to all of the wheels, instead of just to the front or rear. The advantage is that the vehicle can adapt to different driving conditions and transfer more power to the front or back wheels as needed. The disadvantages are that the driveline is more complicated, and the vehicle weighs slightly more.

Many all-wheel drive vehicles are based on a front-wheel drive set-up. They also have a differential in the rear and one in the center of the vehicle that allows power to transfer to the front and rear. A shaft runs from the transfer case to the center differential, and another from the center differential to the rear differential.

Servicing an all-wheel drive at Oil Changers involves servicing ALL of the differentials and inspecting the joints and seals for wear, leaks or damage.

Four-wheel drive vehicles are rear-wheel drive vehicles that have an option to transfer power to the front wheels. In other words, they can be driven as either rear-wheel or four-wheel drive vehicles. These vehicles are specifically designed for the harsh driving conditions that are encountered off-road. The driveline in a four-wheel drive vehicle is similar to that of an all-wheel drive vehicle. The center differential, however, is a transfer case. Maintenance requires servicing both of the differentials and the transfer case, as well as an inspection of the joints and seals.

Vehicle owners would be wise to check with their owner's manual for recommendations on how often to service their vehicle drive train. It's also good to check with your friendly and knowledgeable Oil Changers service advisor as well. You may live in an area where weather or driving conditions require more frequent servicing of the drive train.


Good car care at Oil Changers in New Zealand always includes taking care of your driveline. Without it, your vehicle becomes a very large paperweight.

Oil Changers
PO Box 16686 Hornby
New Zealand, New Zealand 8441
03 3442374