Signs of a Bad Rear Differential

by Jonathan Lister

The rear differential is an integral part of your vehicle that transmits torque and rotation through shafts running the length of the automobile. The rear differential allows all four of the vehicle's wheels to rotate at different speeds which is essential for road traction and stability. When a rear differential fails, it can cause vibration, noise and fluid leaks that impact a vehicle's acceleration and driveability. A driver should consult a certified mechanic to deal with a bad rear differential and prevent further damage to the vehicle's driving systems.

Noise in Gear from an Idle

Man driving car

When the vehicle is turned on and first put into drive, there may be a rattle or clanking noise coming from the rear of the vehicle. This noise may be attributed to the drive shaft universal joints. These joints connect the transmission to the rear differential; and if they have worn down, they could impact the differential by forcing it to work harder, thus wearing down its gears. In order to check the gears of the rear differential, a certified technician will need to be consulted as the procedure requires equipment not commonly available to the consumer.

Grinding Gears at Speed

Mechanic looking at car

When the vehicle accelerates, there may be more noises like a hum or continued clank from the rear. This can be due to the gears in the rear differential being stripped or partially worn which creates an awkward motion as they spin the drive shaft. Noise may be especially bad when the driver accelerates the vehicle quickly and is forced to brake rapidly.

Vibration and Fluid Leak

Mechanic showing car to customer

Worn or ripped universal joints will also cause vibration along the drive shaft and into the engine block via the transmission. This may be felt at high speeds in the body of the vehicle or through the floor. The rear differential and universal joints also have seals and use lubricant to work properly, and a leak or crack in a seal may contribute to vibration and failure of rear differential gears. Look for any fluid pooled at the rear of the vehicle after it has sat overnight.

About the Author

Jonathan Lister has been a writer and content marketer since 2003. His latest book publication, "Bullet, a Demos City Novel" is forthcoming from J Taylor Publishing in June 2014. He holds a Bachelor of Arts in English from Shippensburg University and a Master of Fine Arts in writing and poetics from Naropa University.

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