Every vehicle has at least one differential. It’s a marvelous mechanical device that transfers power from the motor to two wheels at the same time, but allows the wheels to turn at different speeds if necessary.  Whenever you drive around a corner your outside wheels travel a slightly greater distance than the inside wheels.  The differential is the device that ensures good traction and control is maintained as you drive around corners.

A rear wheel drive vehicle typically has one differential located between the rear axles.  A four-wheel drive vehicle has another differential located between the front axles.  A front wheel drive vehicle usually incorporates the differential function inside a component called a transaxle, which also provides the transmission shifting functions.  An all-wheel drive vehicle often uses a transaxle for the front wheels, plus an additional differential between the rear axles.  Any way you look at it, differentials are critical components for your vehicle’s operation. They should therefore be kept in peak condition so your vehicle operates smoothly and reliably.  

Differentials are complex mechanical mechanisms that are lubricated with gear oil.  There is no filter for this oil so it must be exchanged periodically to ensure that small contaminants are removed before they turn into a grinding compound.  Impurities in the gear oil can damage gear surfaces, seals, splines, bearings and bushings, leading to premature failure of the differential and associated components such as axle and pinion shafts. 

Most vehicle manufacturers recommend servicing differentials every 50,000 Km.  If the vehicle is high powered, or used for towing, we recommend more like 25,000 Km.

If you’re looking for a shop that really specializes in differentials, bring your vehicle to Bobs Driveline which is a Differential repair and service shop in Abbotsford.  We provide superior vehicle diagnostics, service and repairs as every team member at Bobs Driveline is fully certified, experienced, and familiar with the latest powertrain technologies.

It doesn’t matter what kind of differential set-up your vehicle has; you want it to be working perfectly. Here are some of the most common signs that your differential needs some attention:

Strange Noises

A failing or bad differential will often make rattling, grinding, or whirring noises.  One particularly common sign of differential problems is that these noises change significantly between vehicle acceleration and deceleration.   Any time you hear an unfamiliar noise from your vehicle we recommend you get it checked out by our auto repair experts.  It could be any number of problems but might include the differential.  Our experts will determine the problem and guide you in choosing the best repair to get your vehicle back on the road and working reliably.

Vibrations

Feeling strange vibrations while driving is another typical indicator of a differential problem.  Vibrations from a differential usually occur when there has already been significant wear or failure of a mechanical component.  Vibrations in the differential can also lead to excessive wear or damage to other components such as universal joints, CV axles, seals, or wheel bearings.

Leaking Differential Oil

This is a tricky one – differential fluid, or gear oil, looks similar to common engine oil.  It is not bright red in color like transmission fluid.  A differential only contains 1 to 2 liters of fluid so it doesn’t take much of a leak to cause problems.  With a rear differential it’s relatively easy to spot a leak because of its location relative to the engine.  A leak in a front differential, or a transaxle, is very difficult to separate from an engine oil leak.  It’s best to have a trained technician take a look at the vehicle from underneath, and possibly remove the differential cover to be sure of the quality and quantity of fluid. 

Differential Service

Like all components of your vehicle, your differential needs timely service. The primary maintenance steps are to change the differential oil, which is also known as gear oil, and to inspect the internals of the differential.  This includes side to side movement, also called float, of the gear carrier.  Too much float will lead to rapid wear of the gears and bushings.  Service inspection also includes assessing the gear contact area.  This is done by a process of painting the gear faces with a special yellow substance and inspecting the contact pattern made by the gear faces as they interface, which removes the yellow substance from the contact area.  This process will reveal many factors about the functionality of the differential to a trained technician.