The Causes and Troubleshooting of a Differential Leak

A differential is a component found in the drivetrain of SUVs and heavy-duty vehicles. Whether the vehicle is a rear-wheel or all-wheel drive, finding leaked fluid in the rear of it indicates a differential leak. The fluid looks like motor oil but has a distinct smell.

What should you do if such a problem occurs? Do you know about the ideal differential stop leak measures?

What Does the Rear Differential Do?

A differential is a gear train featuring three shafts. This component connects to the transmission or transfer case through the driveshaft, transmitting the power of the engine to the wheels.

rear differential stop leak
A differential helps with balance during turns.(Photo Source: cashcarbuyer)

The main function of a differential is to help the vehicle maintain balance during a turn. It does so by enabling the outside wheels to rotate quicker than the inner wheels when the vehicle is taking a turn. The average rotational speed does not fluctuate as the increase in one wheel’s speed is balanced by a reduction of the speed in the other.

How to Repair the Differential Leak?

How do you realize that there is a leak in the differential? You will find grayish or light brown oil under the backside of your vehicle.

The leak could be on the rear differential cover, the axle seals, or the pinion seal. How to stop it and bring the vehicle to the normal running condition? Let’s find out:

Rear Differential Leak Sealer

The easiest and hassle-free option to fix the issue. Instead of spending your time finding the leak source, add some sealer to the differential fluid through the oil fill plug. There are several high-quality leak sealer products in the market. It will repair the leak and restore the seal to the previous condition while you drive.


Replacing the Cover

If the cover is leaking or showing deterioration due to regular wear and tear, changing it will bring the differential to the previous condition. The cover is made of either rubber or silicone and replacing it is quite easy. Just don’t forget to clean the sealing surface before resealing the new one.

Resealing the Sides

This is the way to rear differential stop leak when the fluid drips onto the rear brakes. The task is time-consuming because you have to remove the axle shafts. Then, you have to take the damaged seals out and install the new ones. Put together the shafts to finish the task.

differential stop leak
Take professional help if necessary.(Photo Source: cartreatments)

Replacing the Pinion Seal

Another differential leak could be at the pinion seal. There is a yoke at the front side of the differential, and the surrounding seal can wear out over time. In order to replace the seal, you have to dislodge the yoke and pry out the seal. After that, place a new seal and then attach the yoke to its components.

Sometimes, the problems could be bigger than just a tiny leak. In that case, you may have to replace the whole differential with a new one. You should consult a mechanic if it comes to that point.