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Merchant Automotive MA Billet Coolant Block Off Plate, Duramax | 2001 - 2018


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Product Information

On the rear of the Duramax Diesel trucks from 2001-2018, there is a coolant block off plate. The factory plate is made from cast aluminum and features a gasket for the mating surface. This plate is prone to coolant leakage due to warpage or gasket failure over the years. Merchant Automotive has recognized this problem and created a better solution.

This is the Merchant Automotive Duramax Billet Aluminum Diesel coolant block off plate. This plate upgrades your factory cast aluminum coolant block off plate with a billet aluminum plate that is built to perform better than your OEM plate. It features a 6061 aluminum construction with a black anodized finish. These plates are manufactured in house at our USA facility. To eliminate the chances of a gasket failure, MA has included a built in O-ring on this billet plate. This o-ring provides better sealing and longevity over the factory gasket. It also makes it very easy to install. You will reuse your factory hardware with this new plate.


  • Upgrade For Cast Block Off Plate
  • Great For Replacing Corroded Factory Plate
  • No Gasket Needed


  • 6061 Aluminum Construction
  • Machined In House In The USA
  • Black Anodized Finish
  • Built In O-Ring

Kit Includes

  • MA Aluminum Coolant Block Off Plate

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