Differential & Transfer Case Servicing
Maintain your differential or transfer case in good working order
It’s not unusual for automatic transmission or gearbox specialists to also work on differentials, as the components perform a similar task:
- The transmission or gearbox adapts the engine output to suitable speed and torque to be transferred to the wheels.
- The differential channels that power to the two wheels on the same axle at an appropriate ratio. This is because when the vehicle turns, the outside wheel takes a slightly longer path than the inside one, so has to run that little faster.
The differential sits between the wheels, where the drive shaft connects with the axle. Depending on whether your vehicle is front-wheel drive, rear-wheel drive or four-wheel drive, the differential is on the front, rear or both axles.
In addition to differentials, four-wheel drive cars have a transfer case. The transfer case acts like a differential, but channels power to the two differentials on different axles rather than to two wheels on the same axle.
As in a gearbox, a differential and transfer case require fluid to lubricate the gears, shafts and bearings where metal slides over metal. The oil also transmits heat away from the working surfaces. However, as time goes by, the fluid tends to become dirty or can even be contaminated by water, losing its ability to do its job effectively.
A differential or transfer case seldom give cause for concern in most modern cars, as long as they’re serviced regularly. Servicing requires only a small fraction of the cost of rebuilding or replacing a differential.
What the service includes:
- Drain differential gear oil
- Inspect the oil for evidence of sludge
- Fill the differential with new oil of the correct type
- Reseal differential cover if needed
- Check for leaks and wear on seals
- Test to check working of serviced differential.
While a differential or transfer case is a relatively straightforward mechanical device, it’s worth making sure that nothing goes wrong with them.
Differential & Transfer Case Rebuilds & Repairs
Maintain your drivetrain all the way to the axle
Your differential or transfer case needs to operate efficiently to transfer the torque coming out of the transmission to the wheels. Differential faults or transfer case problems will see your vehicle operate at reduced power or not at all.
The differential sits on the drive axle and regulates the power to the two wheels on that axle. On a standard rear-wheel drive car, for instance, the outer wheel has to travel a slightly longer distance when you turn and therefore needs more power.
A four-wheel drive vehicle also needs a transfer case in addition to differentials on both axles. A transfer case does a similar job as a differential. It splits the torque between the front and rear axles. Some transfer cases operate part-time to allow more economic two-wheel driving when four-wheel drive isn’t needed, while others are engaged full-time. Some of the latest transfer cases can automatically shift from two-wheel to four-wheel drive, depending on driving conditions. Transfer cases can be gear driven (mostly for larger or hard-working vehicles) or chain driven (popular for lighter and recreational vehicles).
The most obvious early signs of trouble with a differential or transfer case are knocking or clunking sounds, rumbles or oil leaks.
How we rebuild & repair your differential or transfer case
Diagnosing what’s wrong always comes first. Sometimes this can be done without any major dismantling. When we do have to take apart the differential or transfer case, we strip it right down and inspect each part for damage. Any unserviceable components are replaced with new or reconditioned parts. Those that pass our tests are cleaned and returned to the assembly.
Depending on the extent of the fault in your differential or transfer case, it may be more cost-effective for you to exchange the entire unit rather than repair or rebuild your original. Our technicians will advise you if you need an exchange differential or transfer case once we’ve determined how serious the problem is.
Whether we repair or rebuild, we always test your differential or transfer case to ensure it works perfectly.