Why You Should Repair Your Differential

What is a differential?

The differential on a vehicle allows the wheels to spin at different rates to maintain traction. For more information on differentials, check out our How Differentials Work series of articles. We go over the components of front and rear differentials such as the differential gears. Also, what differentials do. And we also go over standard differentials, locking differential, hydraulic locking and more. If you need to calculate the gear ratio, check out our differential gear ratio calculator.

What goes into a front and rear differential repair?

As you use your vehicle, your differential will wear and tear normally over time. This damage or damage from an accident will mean that your differential may need to be repaired. There are two main methods to fix a differential. These are rebuilding and remanufacturing a differential. Both methods require the differential to be dismantled, cleaned and thoroughly inspected. For a differential rebuild, we will repair as many parts as possible unless the part needs to be replaced because of damage. Then, for remanufacturing the differential, any part that is damaged or worn out is replaced with a new replacement. In extreme situations, a differential replacement may be required. Contact us and let us help you!

Causes of Differential Failure

How does a differential fail? There are multiple sources for differential damage leading to a differential failing. These issues will affect both a rear differential and a front differential.

Not enough lubrication

For a differential, like an engine, lubrication is important. The differential fluid is also known as differential oil or gear oil. It is vital to maintaining the temperature. If your rear differential is low on oil, it can cause damage to the components in the differential. Also, it can cause the differential to overheat because of the metal components making contact with each other component.

Using the incorrect lubricant

If the wrong lubricant is used in the differential, it can cause the oil to not have the right viscosity for the components. This can cause not enough lubrication in parts or if the viscosity is too high it can cause increased drag. This can lead to long-term damage to the front differential or rear differential.


Accidents are probably the most obvious cause of damage to a differential. A minor fender bender or even driving over a large pothole could cause some damage or cause the seals to fail. Fluids in the differential could then start to leak. If you have been in an accident, take your vehicle to your mechanic of choice and ask them to check your differential, especially if you see fluids leaking after the accident.

Water entering the differential

If water gets into the differential it can cause some major issues for the differential fluid. The oil will emulsify with the water which will then develop rust inside the differential. Water getting into the differential could be a result of the oil seal failing, or driving in high water.

Symptoms of a damaged front or rear differential


There are a wide variety of symptoms that occur depending on the kind of damage and how severe the damage has been done to the differential. A lot of issues that may need differential repair can be diagnosed with sound. For example, a whining noise or a humming noise usually is from the differential gears. Also, a clunking or grinding sound comes from damaged bearings.

Tire wear

Some other symptoms of a damaged differential relate to how it affects the tires. The differential may not be properly distributing the power to the wheels evenly. This causes excessive tire wear to one tire as there may be too much power on one of the left and right wheels.

Other symptoms

Damage to the differential may cause a differential fluid leak. Low amounts of differential fluid can damage the differential and may be caused by damaged seals. Also, if it is damaged you may feel a clunking feeling while shifting. Steering the vehicle may also feel more difficult.

How much does front differential repair cost?

The differential repair cost is determined by the severity of the damage. Also, the differential repair cost is affected by what is damaged. For example, the rear differential repair cost is more when replacing or repairing the differential gears than fixing a leaking differential. As a result, major repairs will cost quite a bit more. Differential replacement cost is more expensive as well. For exact pricing, contact us and we can provide more information.

How to check the differential fluid

First, locate your differential which is located underneath your vehicle. On the differential, there will be two plugs, the fill plug and the drain plug. The fill plug will be higher up on the differential. The fill plug will also have a tag on it. Following that, place a pan underneath the differential. Then, using a wrench or a socket remove the fill plug, fluid might come out of the fill plug. If not, then, using a wire or a finger with a glove on it, check to see how much fluid there is by putting it below the fill plug. If there is no oil, then you will need to fill the differential.