Repairing Your Car’s Rear Differential? Here’s What You Should Do…

Your car’s rear differential is vital for its functioning.

It has be sturdy and reliable. It’s necessary to ensure that power gets transmitted correctly from engine to transmission.

Now, to maintain its reliability, you have to change the oils regularly. You also have to pay attention to minor disturbances in its functioning.

So To Start Off – What’s a Rear Differential’s Function?

A rear differential takes the power of the engine (which is longitudinal), and then transmits those to the wheels using a driveshaft.

This is done with the assistance of gears, which supply the 90 degrees switch in direction change on the car’s rear axles. This power transmission is what allows a car to propel ahead.

In essence, without a rear differential, your wheels don’t move.

Basic Sign of Rear Differential Malfunctioning – Odd Noises

It happens, especially if you don’t give you rear differential much thought. And in those situations, you’ll need to get to repairing.

Now what type of noise indicates a malfunction?

Usually, you’ll hear clicking sounds when you start to turn. And every now and then, you might hear a whirring sound from your vehicle’s back.

If you see those basic signs, then it’s time for a rear differential repair.

Rear Differential Symptoms in Detail

Usually, you’ll notice two basic symptoms. And those symptoms are…

Constant Back Noise

If you pick up on howling from the back of your SUV or truck, then it might actually come from the rear differential. You might notice a pitch change, in addition to a noise that comes and goes.

The seriousness of the noise can change depending on the load on your car’s differential. The more your car carries, the more likely it is to make that noise.

Differential Leaks

Normally, issues of differential leaks occur as a result of low rear differential oil. In those situations, leaks occur at the following locations…

• Axle Seal.
• Pinion Seal.
• Rear Differential Cover.

You might notice a gray or light brown fluid on the ground, or below the back of your truck. And this indicates a fluid leak.

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How much you’ll pay to fix a leak depends on the seriousness of the issue. Sometimes, a seal replacement or backlash adjustment is all you need. In other situations, you may need to change the entire differential.

Rear Differential Repair Types

If the there’s an oil leak, then apply one of the repairs below. And those repairs include…

Side Seal Replacement

Here, the seals stop the differential fluid from leaking behind into the rear brakes. Switching this seal is a little difficult, since the axle shaft has to be removed.

Old seals are pried out, and new ones are added before the car is reassembled.

Rear Gasket Replacement

The cover is normally made from rubber or silicone, so it’s liable to deteriorate.

Fortunately, this is easy to repair. All that’s necessary is to remove the cover and clean before resealing.

Rear Pinion Replacement

This attaches to the differential’s front. It’s a yoke that’s positioned in the driveshaft. The seal around the yoke may develop over time, due to nicks in the rubber, or as a result of age.

More time may be required to repair this. The yoke needs to be taken out, the seal pried, and a new seal should be added into place.

What Are the Rear Differential Repair Costs?

The majority of bearings and seals are quite cheap. If you combine them with the hours of labor needed to replace them, you should expect a cost that’s between $200 and $400!

If a gear set is needed, that number may jump up a little bit. A rear differential repair that uses new gear sets may go over $1500!

In fact, the $1500 value is for good condition but used assembly. If you’re seeking a new differential, expect prices to fall between the $3000 to $4000 ranges!

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As you can tell, what you pay varies widely. As such, regular maintenance of your rear differential is vital!

Servicing a Rear Differential

The gears within your rear differential are filled with oil. This oil is a necessity to lubricate the bearings and gears, which cools them down. And this prevents overheating.

That fluid may go bad over time. And the result is, it breaks down the mechanism where metal filings from the bearings and gears might collect in the fluid.

That’s one of the reasons why regular oil replacements are a necessity. A gear oil change is always required to ensure that gears aren’t damaged from the inside (which is what the pinion and ring gear seals are for).

How Often Should I Service?

It depends. We recommend servicing every 20,000 to 40,000 miles.

The greater the load that your car carries, the sooner you’ll need a service. Done frequently, you won’t have to worry about damages which can cost you thousands!