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It's become common knowledge that factory differential covers are barely adequate for stock truck duties. For those that have more power, tow more or want to help extended the life of their differential, Fast Coolers has a great solution for the Ram and GM trucks running the AAM 11.5/11.8 rear differential know as the Fast Filtered Cover. Yes, many different covers out there claim to do those same things but why go with a Fast Filterd? Here are a few reasons why:

  • Double the surface area internally to better radiate heat away from the oil.
  • More fluid capacity while keeping the same fill levels to ensure that all of the bearings and seals are getting lubricated as designed by the factory.
  • An external 40 micron sand cast filter that can be swapped without taking off the cover. This ensures that you're getting clean oil cycling through your differential. The filter is fed oil that is being slung up by the ring gear that travels through a hose to the filter housing. From there, it drains back into the bottom of the cover so that you have a rotation of oil being filtered while your ring gear is spinning.
  • Ports for temperature sensor and drain plug along with having a sight glass.
  • Fluid changes are done through the external filter housing and do not require removal of the cover giving you years of clean, mess free fluid changes!


All of these things combined give you rear differential cover that cools faster and longer while running cleaner. This helps ensure that your axle does not wear out prematurely along with being able to provide better performance and longevity. If your serious about your rear axle peroformance on your Dodge Ram or GM, you'll be hard pressed to find a better performing cover available!