How Long Can You Drive With a Rear Differential Leak?

If your car is making strange noises or if you are having difficulty controlling it, one of the reasons can be a rear differential leak. At first sight, this may seem like an easy fix but when left unchecked for a long time there can be major issues.

How long can you drive with a rear differential leak? We will talk about this and more.

What is a rear differential leak?

The main purpose of a rear differential is to allow the rear wheels to rotate at different speeds while still providing power from the engine to the wheels. A rear differential leak is an oil leak that happens in cars with the rear wheel drive (RWD). This can cause your car to lose power and break down over time.

How long can you drive with a rear differential leak?

The amount of time you can safely drive with a leak depends on several factors, including the severity of the leak, the type of vehicle you have, and your driving conditions.

In this example, you cannot call it a leak but a mere weep. There is nothing to worry about since a weeping rear differential is common in most 10+ year old trucks. But you should still take a look every other week to see if it turns into a leak. After all, you don’t want to turn this into a costly repair.

Here is a moderate leak where you can still drive safely for a few weeks to a few months. But you need to go to a mechanic soon enough before the leak worsens and causes more damage to your car.

This is when things are out of hand and you need to fix the leak as soon as possible. You can still drive for a while without a repair but that depends on the severity of the differential leak.

If you are not sure about the severity of your rear differential fluid leak, it’s best to be cautious and get it fixed as soon as possible. After all, the leaking fluid can damage your engine and other components.

What happens when you drive with a rear differential leak?

When you drive with a leak, the fluid levels in your car start lowering, which causes the gears to grind and overheat as time passes by.

If the gears reach extreme temperatures, they fuse together and permanently damage your differential. Driving with a rear differential leak also affects your tires as they overheat and their lifespan is shortened.

What causes a rear differential leak?

Most differential leaks happen when the components mentioned below are damaged. These usually happen through erosion over time or other metallic corrosions.

• Bad differential gasket: The differential gasket works as a seal between the differential case and cover.
• Rear differential pinion seal: The pinion seal is located at the rear differential and it is used to seal the area where driveshaft enters the differential.
• Differential cover: This protects the internal parts of the differential from water entry and other damage. Differential covers mostly get damaged by corrosion.
• Bad differential side seals: The side seals are on each side of the differential and they function to seal the bearings in the proper place.
• Leaks in differential tubes: Differential tubes carry differential fluids from the differential to the axle. Differential fluids should be carried to the axle because low levels of fluid can damage the moving part of the axle. Leaks in the tube may result in a loss of fluid.
• Worn Axle seals: The Axle seal is situated where the axle meets the differential. This seal stops the differential fluid from leaking through the axle.

How to fix a rear differential leak?

Now that you know how long can you drive with a rear differential leak, it’s time to fix the issue. First you have to identify the source of the leak. If the leak is in the rear differential seal or gasket, you have to replace it. If the leak is caused by a crack in the differential housing frame, you will need to weld it shut.

If the source of the leak is identified and repaired, clean any oil that leaked. This will prevent further damage to the differential. Lastly, you need to check how much rear differential leaking fluid has been lost and then add more fluid if necessary.

Rear differential leaks are serious issues that need to be repaired as soon as possible. Depending on the size and severity of the leak, you can ride your car for a short time but it is not advised to drive with this leak for too long. We recommend that you fix the problem as soon as possible and not damage your vehicle any further.

FAQs

1. What happens if I run out of rear differential fluid? 

Ans. Usually rear differential fluids are changed every 30,000 to 60,000 miles. After 50,000 miles most differentials require a fluid change. If the fluid gets too low or runs out, the differential starts making noises and eventually stops working. When that happens, the gears are seized that causes the car’s rear wheels to lock up and potentially cause an accident.

2. Can bad rear differential damage transmission? 

Ans. In rear wheel drive vehicles, the rear differential and transmission are separated using the drive shaft. Causing damage to one of these parts does not affect the other one.

3. Can I drive my car with a bad rear differential? 

Ans. It may not be the safest option but you can still drive with a damaged rear differential. Waiting to repair the issue may further damage other components of your vehicle. This can cause more issues to your car over time and result in more expensive repairs in the future. We highly recommend that you get the bad rear differential fixed as soon as possible.

4. What are the symptoms of needing differential fluid change? 

Ans:

• Strange noises like grinding or humming when car is moving
• Vibration or shaking when driving
• Difficulty making turns or steers
• Fluid leaks

5. How much does it cost to replace differential fluid? 

Ans. The average cost to replace differential fluid is $80 to $150 if you go to a mechanic.

• Parts- $20-$25
• Labor cost- $60 to $100

We recommend that you contact a reliable mechanic or repair shop in your area to get a more accurate estimate relevant to your location.

6. How long should I wait to drive after my rear differential leak is repaired?

Ans. After you replace your rear differential leak, you are advised to wait at least 30 minutes before you drive. This allows the new parts installed in the car to settle in and function properly.