Driveline Repair / Rear Differential

Rear Differential Service, Repair, Replacement

Rear Differential/Ring and pinion gears – Rear Wheel Drive/All-Wheel Drive cars

Changing the oil in the differential is often overlooked as a regular maintenance task but it is very important for the life of your vehicle. Most rear-wheel drive light trucks, SUV’s, and passenger cars have a rear differential and the housing contains a dark, heavy oil that lubricates the moving parts inside. If this oil starts to leak and the lubrication fails, you will not get very far for very long. Fortunately, unlike your engine oil, you only need to change the differential oil every 30,000 to 50,000 miles (check your owner’s manual).

The differential is designed to compensate for the difference in distance the inner wheels and outer wheels travel as the car goes around a corner.
Front-drivers typically integrate the differential in the transmission housing and share the same fluid. The differential oil lubricates the ring and pinion gears that transfer power from the driveshaft to the wheel axles. If your car is fitted with a limited-slip differential, it also keeps all the moving parts in that assembly healthy. Changing this oil is just as important as changing your engine’s oil, and for the same reason. Metal-to-metal contact wears down surfaces and creates heat from friction, which inevitably weakens the gears and leads to failure. Checking and changing the differential oil in a light truck is actually pretty easy, and it’s only a bit more difficult in a car. In either case, this small procedure can save you a big headache down the road.
You may have seen a pickup truck with a large tear-drop shaped metal housing that connects the rear half axles to the center drive axle. This is called the rear-differential. This is where the ring and pinion gears are located. The ring and pinion gears serve two purposes. First, it translates the transmission rotation 90 degrees to drive the wheels. Second, it slows the rotation speed out of the transmission to a more useable wheel axle speed, while increasing available torque. When you hear people refer to numbers like 3.08, 3.73, or 4.10, they’re talking about the ratio of the ring-and-pinion gears in the rear axle—hence, the numbers are more accurately 3.08:1, 3.73:1, or 4.10:1. … That also means that for every one turn of the ring gear, the pinion will turn 4.10 times. Problems do not normally occur in the ring and pinion gears unless there is an unusual amount of stress. If the gears are not properly lubricated or excess stress causes chipping, the ring and pinion will need to be replaced.

Sprider gears

Spider gears are a part of your car’s gear set allowing its rear wheels to turn at different speeds when necessary without affecting the movement of the car as a whole

Limited slip differential unit

A limited-slip differential prevents excessive power from being allocated to one wheel, and so keeps both wheels in powered rotation, ensuring that the traction will not be limited to the wheel which can handle the minimum amount of power.
Wheels receive power from the engine via a drive shaft. The wheels that receive power and make the vehicle move forward are called the drive wheels. The main function of the differential gear is to allow the drive wheels to turn at different rpms while both receiving power from the engine.

At All Auto, we pride ourselves on correct diagnosis of all driveline and axle issues.

• Axle Repairs
• Differential Repairs
• Drive Shafts /Universal Joints
• All-Wheel Drives
• Transfer Cases
• Engine & Transmission Mounts
• Automatic Transmission Diagnosis & Repair
• Clutch Diagnosis and Repair
• Drive-Shaft Replacement
• Differential Flush Service