A leaky rear main seal can be one of the most frustrating leaks on a vehicle. Many small oil leaks can go unnoticed for long periods of time and cause very few problems in the day to day operation of your vehicle. A rear main seal leak, on the other hand, can quickly cause a lot of problems. First, your rear main seal is the lowest seal in your engine so even a small tear or deformation in the seal can cause a very high leak rate. High oil leak rates can cause dangerously low oil levels in your vehicle very quickly leading to permanent engine damage. The other problem with a rear main seal leak is that it is so low on your vehicle that dripping oil will be blown back onto your transmission, chassis, electrical wiring and other important components on the bottom of your vehicle while you drive.
Oil covering the underside of your vehicle may not seem like a bad thing at first, but it can cause lots of problems for your vehicle. Oil covered components can start to attract road grime and dirt which can start to cause things to gum up and possibly malfunction. Also, electrical wiring is safe from oil as the insulation used in automotive wiring is oil resistant, but the plugs, connectors and junctions can easily fill with oil and cause degradation of the plugs, plastic and connections.
For these reasons it’s important to make sure you fix your rear main seal leak to help keep your car safe. In order to fix a rear main seal leak it helps to understand why the leak has started.
Causes of a rear main seal leak:
The Rear Main Seal in your car is the seal at the back of the engine that surrounds the crankshaft and keeps the engine oil contained while your engine is running. The first way this seal can get worn out is from a lack of use. As your engine is running, oil is splashed onto your rear main seal and the oil helps keep the seal soft and clean due to the conditioners and detergents in your oil. Without this regular oil bath, seals can quickly dry out and crack or lose their form. Also, as an engine sits without running for long periods of time, the crankshaft can cause deformation in the seals on the bottom causing a leak when the engine starts and the crankshaft begins to spin again.
Low engine oil level or excessive engine wear also can lead to a rear main seal leak. A low oil level will leave the crankshaft spinning on the seal without any lubrication that can lead to excessive wear and a leak. Also, excessive engine wear can leave metal particles suspended in your oil which can quickly cut away at your rear main seal leading to a leak.
Lastly, high mileage and normal engine wear can lead to a rear main seal leak. No matter how good of a job your oil does lubricating the rear main seal and even if all other conditions are perfect, your rear main seal will slowly wear down due to the contact with the spinning crankshaft.
In any of these cases, your rear main seal is most likely salvageable. Whether it is from normal wear, a lack of use or other reasons, your rear main seal can be restored to its original size and sealing capability by using BlueDevil Rear Main Sealer. BlueDevil Rear Main Seal is a chemical sealing agent that will be absorbed by your rear main seal. This will cause your rear main seal to return to its original size and shape sealing your leak and protecting your engine and vehicle.

For more information about BlueDevil Rear Main Sealer, check out our product information page here: Rear Main Sealer.
You can find BlueDevil Products, like our Rear Main Sealer at any of our partnering local auto parts stores like:
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rear_main_seal_leak.jpg – by Christos Georghiou – Licesnsed By Thinkstock Photos – Original Link