Sinister Diesel 2001-2016 Duramax, Coolant Reservoir (Degas) Cap – SD-DC-DMAX-01


Product Highlights:

This new Coolant Reservoir (Degas) Cap functions like a factory cap, but features custom Sinister Diesel looks. The cap fits OEM or Sinister Diesel Coolant Reservoir for the 2001-2016 GM Duramax. It is made from CNC machined, solid billet T6-6061 aluminum with an interior pressure relief system, so it will continue to function even in case of a gasket failure. Available in gray or Sinister Blue, this cap looks as good as it works!

Vehicle Fitment

2001-2016 GM Duramax 6.6L

Key Features

  • Cap is rated for 15 PSI
  • Available in Anodized Sinister Blue or Gray
  • CNC Machined from T6-6061 Billet Aluminum
  • Etched Sinister Diesel Logo
  • Replacement for failure-prone factory cap
  • Fits 2001-2016 GM Duramax Coolant Reservoirs
  • Lifetime Sinister Diesel Warranty


  • (1) Sinister Diesel Coolant Reservoir Cap

*Special Order. Please allow for additional shipping time.