3 Causes of ford F105 Rear Main Seal Failure – (& Replacement cost)

Rear seals are not very expensive but the labor cost is pretty high. A rear main seal will cost around 15$ to 100$ and the labor cost will be around 500$ to 600$. In total, It will cost around 600$ to 700$ to replace your Ford 150 rear seal.

The Rear main seal is used in the back of the engine to hold the fuel and to prevent it from spilling out or leaking. The rear main seal is placed at the connecting point of the crankshaft and the transmission system. It operates as a jacket to fuel. There are so many reasons which can cause the fuel to leak or spill and cause an accident. A rear main seal helps you to avoid these hazards.

Rear main seal leakage is very dangerous for your engine and your vehicle. Not only can it cause a devastating accident, but also it can immediately set your vehicle on fire. Normally it happens because of the poor sealing system and high oil pressure in the engine. But you can easily replace it.

Ford F150 Rear Main Seal replacement cost

3 most common Causes of ford F105 Rear Main Seal Failure

There are so many things that can cause rear seal leakage. You have to use a good quality seal to protect your engine’s oil leakage. The main culprits behind the rear seal failures are:

#1 – Long Aged

One of the major reasons behind a rear seal failure is its long age. After a period the seal deteriorates slowly. Therefore, you should not use a rear seal for a very long period.

#2 – Excessive Use Of The Engine

The rear seal can also deteriorate when the engine heats excessively.

#3 – Long Leisure

The rear seal gets automatically damaged when the engine or vehicle is not used for a long period.

Some other issues can cause damage to the rear seal-

  • Constantly running the engine on low fuel
  • De hydrated engine
  • Driving on a rough and tough surface

4 most common Symptoms Of A Rear Main Seal Leakage

As soon as you get to know that your rear main seal is damaged, you have to replace it immediately.But how can you tell whether it is damaged or not?

Here are the symptoms of a damaged rear main seal-

  • Oil mark on the road surface
  • Traces of oil underneath your vehicle
  • Frequent need forfuel
  • Constant low mileage

Price Of Different Rear Main Seals For Ford 150 in average

You will find 12 to 15 types of rear main seals to choose from. You can find these at your local workshop. Rear main seals can be bought from Ford’s official showrooms. Let’s take a look at the list of some rear main seals’ prices

S.LName Of The SealPrice Range
01.Multipurpose seal 25$ to 30$
02.Felpro seal set15$ to 20$
03.One part rubber seal30$ to 35$
04.Dual part rubber seal30$ to 40$
05.Rear axle seal (National)40$ to 45$
06.Felpro triple seal50$ to 55$
07.GM rear axle seal60$ to 70$
08.JK dual seal (rear axle)80$ to 90$

Procedure Of Replacing A Rear Main Seal

Though a rear main seal does not cost very much, the labor cost is comparatively very high. This is because of the procedure. The procedure is very complex and time-consuming. You have to pull out the whole engine to replace the rear main seal.

The seal size varies from engine to engine. So, you have to be careful about the fact that, you bought the properly sized rear main seal. Otherwise, the seal will not prevent the fuel from leaking.

At first, you have to pull out the whole engine and remove the bolts and the outer plate of the engine. Then you can remove the old seal. At this stage, you have to thoroughly clean the outer portion. For, if you do not clean it properly, the debris will not allow the seal to fit tightly. Then you can put the new seal.After this, you can clean the inner part and put back everything together.

People often stand back from this complex procedure, and the result is frequent calls that ask me to deal with the matter.

So, keeping that in mind, I am sharing with you a visual guide of the detailed procedure for replacing the rear main seal.

Frequently Asked Questions (FAQs)

1. Is It Safe To Drive With A Leak Rear Main Seal?

It depends upon your situation. You can easily drive around 90 miles to 110 miles with a leakage in your rear main seal. You can drive even longer ona cool surface. But you should replace it as soon as you can. Because driving with a damaged rear seal is very dangerous. If the surface is hot, it can even cause fire to your engine.

2. How Long Does A Rear Main Seal Last?

A rear main seal can last around 4500 miles to 5500 miles. It depends on your use and your seal’s quality. A good quality rear seal can last up to 6000 miles. It also depends on fuel level. When you constantly drive at a low fuel level, the seal gets dehydrated and gradually tears apart.

However, no matter how you use it or what is your seal’s quality, you should change it after every 5000 miles.

3. How To Find Out The Rear Main Seal In the Engine?

Finding the rear seals is very difficult as these things are situated at the most remote part of your vehicle’s engine. It is normally found at the connecting point of the crankshaft and the transmission system. But some engines use additional seals at the outer part of the fuel tank.

You can easily find the outer seals by simply looking at the opening of the fuel tank. To find out the inner seals, you will have to remove either the engine or the transmission system.

Check this video tutorial to get help on the matter.

Take Away

Although Ford useshigh-quality rear main seals for its fuel tank, the seals can be damaged very often. It is a very common issue in every vehicle. However, you can easily replace it. The seal does not cost much. But the labor cost is the main concern.

As the process of replacing the rear main seal is very critical and time-consuming, the mechanics take a good deal of money for this. Where you can buy the seal for under 100$, you have to spend 500$ to 600$ on the labor cost.

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Mahir Ahmed


I'm the guy responsible for ensuring honest, informative, accurate and helpful guide to the reader.

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