Rear Main Seal Leak Causes

Rear Main Seal, Rear Main Seal Leak CausesRear main seal leaks can happen in any vehicle but seem to be more prevalent in some rather than others.  Before you buy a used car, it can be worth doing some research to see if the vehicle you plan on purchasing is prone to rear main seal leaks.  Since some vehicles are more prone to these leaks, it would make sense that manufacturing and engine design can be one of the rear main seal leak causes, but there are a few others.

Rear Main Seal Leak Causes

  • Low oil level
  • Old Age
  • Normal Wear
  • Lack of use

Low oil level

As with any oil seal a low oil level can quickly cause a leak.  Low oil levels can cause excess heat at the seal which can deform and damage the rubber causing a leak.  Also, engine oils contain special conditioners to help keep the seals in good condition so a lack of oil can dry out the seal.

Old Age

The materials used to make seals, unfortunately, doesn’t last forever.  Over time the seal will get brittle, deformed, lose its elasticity and will lose the ability to hold oil inside the engine.  If you are restoring or rebuilding an old engine, it’s always smart to change the rear main seal to prevent a leak.

Normal Wear

The rear main seal has the crankshaft spinning inside it at thousands of RPMs every time you drive.  Eventually, the metal crankshaft will win against to rubber seal and a leak will occur. On some vehicles, this can occur as soon as 100,000 miles while others can drive half a million miles or more before the rear main seal starts to leak.  Either way, metal beats rubber and rear main seals will wear out.

Lack of use

The most common of the rear main seal leak causes is lack of use.  If your engine sits idle the rear main seal doesn’t get the benefit of the conditioners in the oil we mentioned early, but the lack of motion of the crankshaft will also cause constant stress on the seal leading to deformation and a leak next time you start your engine.

So What Do I Do With a Rear Main Seal Leak?

No matter what cause of your rear main seal leak, there is an alternative to the hard part replacement if that doesn’t make sense for your vehicle.  Simply add Blue Devil Rear Main Sealer to your engine oil and drive like normal!  BlueDevil Rear Main Sealer can remain in your engine oil until your next oil change and will recondition your rear main seal restoring its sealing power keeping your vehicle leak free!

You can pick up BlueDevil Rear Main Sealer at one of your local auto parts stores like:

  • AutoZone
  • Advance Auto Parts
  • Bennett Auto Supply
  • CarQuest Auto Parts
  • NAPA Auto Parts
  • O’Reilly Auto Parts
  • Pep Boys
  • Fast Track
  • Bumper to Bumper Auto Parts Specialists
  • S&E Quick Lube Distributor
  • DYK Automotive
  • Fisher Auto Parts stores
  • Auto Plus Auto Parts stores
  • Hovis Auto & Truck Supply stores
  • Salvo Auto Parts
  • Advantage Auto Stores
  • Genuine Auto Parts stores
  • Bond Auto Parts stores
  • Tidewater Fleet Supply
  • Bumper to Bumper Auto Parts
  • Any Part Auto Parts
  • Consumer Auto Parts

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rear_main_seal.jpg – By FabrikaCr – Licensed By Getty Images – Original Link