Wheel bearing leaking oil! Several reasons cause the oil to leak through the wheel bearings. Leaky wheel seals, damaged axle tube seals, and defective wheel bearings are the culprits responsible for fluid leakage through the wheel bearings.
Below, we will describe each of them and provide the solution as well to fix the oil leaking issues. Turns out, we will also break down the underlying reasons that cause wheel seals to leak. Without further ado, let’s dive into this article.
Wheel Bearing Leaking Oil [3 Easy Solutions]
Why does wheel bearing leak? Then, this chapter will reveal all the reasons that will cause wheel bearing to leak.
1. Leaky Wheel Seals
Leaky wheel seals or bearing seals are the main culprits that cause the oil to leak out of the wheel bearing.
Generally, the bearing seals have two duties. First off, they prevent dirt, dust, and contaminants from reaching the internal parts of your vehicle or wheel. Second, bearing seals prevent the fluid or lubricants from coming out. If they get worn out or leak, oil starts leaking out and dirt and dust can easily enter the wheel. Consequently, it reduces the life of your car bearings.
Wheel seals get damaged due to clogging hubcap vents or axle vents. As the fluid or oil in the wheel end gets heated, it starts building pressure and the pressure should be released somewhere. Generally, the pressure gets released through the hubcap vents or axle vents.
If both the two vents get blocked, the pressure will find another way to discharge itself and it’s usually through the bearing seals.
Apart from these, there are several reasons that cause your wheel seals to leak. We will break down them in the next chapter: What Causes A Wheel Seal to Leak? So, keep reading.
You can easily stop the oil from leaking through the bearing seals. Just replace the worn-out wheel seals and walk away. If you don’t know how to replace bearing seals, check out the following tutorial.
Alternatively, you can bring your car to a mechanic to replace the bearing seals if you are not mechanically inclined.
2. Oil Actually Comes Out of Axle
Sometimes the oil coming out of the bearing is actually leaking from the axle. A worn-out axle tube seal is the culprit responsible for axle oil leakage. You can find the seal at the end of the axle tube. It’s sandwiched between the braking elements and the wheel bearings.
The seals get exposed to heat on both sides. Besides, the seal is touching the spinning axle shaft which creates friction heat. Both these reasons are enough to damage the axle tube seals. To get a better idea about axle oil leaks.
It’s a bit challenging to replace the axle tube seals because you need to pull out the wheels, braking components, and the axle itself. So, most mechanics suggest replacing the brakes along with the damaged seals.
But if you are a DIY nerd and want to do the task by yourself, you can watch this tutorial to learn how to replace Axle seals.
3. Faulty Wheel Bearings
Wheel bearings have no relationship in terms of leaking a seal or axle seal. However, sometimes a bad wheel bearing, especially the rear one can leak the axle seals as the defective wheel creates extra vibration. On top of this, a faulty bearing allows the shaft to move or spin vertically in the seal and cause a leak.
First, you need to replace the defective wheel bearings with new ones. Then, you should replace the axle seals and the bearing seals as well.
Apart from these, you can also experience the oil leak coming out of the hub bearings. If the wheel bearings get loose, they allow the seals to wallow on their sealing surface. Consequently, the oil can easily escape from the wheel bearings. To solve this issue, just tighten up the bearings.
What Causes A Wheel Seal To Leak?
Several reasons are responsible for a wheel seal leaking. They are:
1. Seals Are Not Aligned On The Spindle Or Within The Hub
Proper seal installation is a must to prevent future seal leakage. And lining up the seals on the spindle or within the hub is a prerequisite for appropriate seal installation. Before installing the seals, inspect the seals to see whether it’s aligned on the spindle or not.
In this case, you can gently move the bearing seals on the spindle shoulder and check whether there is any gap between the spindle and the inner diameter of the seal.
On the other hand, if the seals are for the hub mount, ensure you keep the seals over the hub and inspect for a gap. If every line of the seal fits snugly, you need to install the seals.
2. Install The Seals In Improper Direction
Wheel seals will cause a leak if you install them in an improper direction. Before installing them on the spindle, ensure you place the right side of the seals on the spindle or into the hub. Generally, you can find a text on the seal that tells you which is the oil side and which is backward. If your seals are installed backward, it will cause oil leaks.
3. User Improper Tools To Install The Seals
Using the right tools to install the wheel seals is completely a game-changer. Every seal box will recommend a tool number to complete the installation correctly. Fortunately, you can find hand-installable seals in the market. They don’t require any tool to install.
4. Incorrect Bearing Adjustment
Incorrect bearing adjustment is another caveat responsible for wheel seal leakage. Most car owners make the mistake of adjusting the bearing with an impact wrench. It will either over-tighten the wheel bearing or under-tighten it. If you overtighten the wheel bearings, it will impact the seals and leak them. We recommend you adjust the wheel bearings using a breaker bar with proper socket size.
5. Worn-out or Damage Components
Most car owners make the mistake prior to installing the bearing seals by not checking other components for damage. Dirty and damaged wheel bearings will hurt the seals and cause a leak. So, we recommend you inspect other components before installing the bearing seals.
Can I Drive With A Leaking Hub Seal?
Yes, you can drive with a leaking hub seal if the leak is small. In other words, it’s ok to drive with a leaking hub seal depending on the size or diameter of the seal. But the question is- how long can you drive with a leaking wheel seal? If the fluid is not leaking out like crazy, you can drive the car for a few days. However, we don’t recommend you to drive your vehicle for a long time with a leaking seal. Otherwise, it will cause permanent damage to your transmission, which requires a lot of bucks to repair.
How Much Does It Cost To Replace A Wheel Seal?
Generally, it will cost you around $236 to $288 to replace axle shaft seals. The labor cost falls between $196 to $247 based on location. And you need to spend $40 on parts. However, if you install the wheel seals by yourself, it will take $40 bucks from your wallet.
Do wheel bearings come pre-greased?
Generally, wheel bearings don’t come pre-greased. You need to lubricate them. However, some manufacturers like Timken offer pre-assembled bearings that come pre-greased.
How long does it take to replace a wheel seal?
Depending on your skills, it will take a maximum of 2 hours to replace wheel seals.
Can wheel bearings catch fire?
Yes, wheel bearings may catch fire if you fail to lubricate them or the wheels get dirty.
Damaged bearing seals or leaky wheel seals are the main culprits that cause the bearings to leak oil. Therefore, defective axle tube seals and worn-out wheel bearings are also responsible for leaking oil through the wheel bearings. Fixing those issues will help you stop the oil leakage.
Note: You can also read how to fix Kohler command engine oil leaking problems.