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Heating and Cooling› Thermostats, Housings and Fillers

Sinister Diesel

Sinister Diesel 01-16 GM Duramax 6.6L Coolant Reservoir (Degas) Cap - Gray

$116.99 $99.99 Save $17.00

SKU: S004 SD-6.6DC01-GRY

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Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Description

The Sinister Diesel Coolant Reservoir (Degas) Cap is a replacement part for 2001-2016 GM Duramax 6.6L vehicles. This cap functions like a factory original but features custom Sinister Diesel styling. It is constructed from CNC machined, solid billet T6-6061 aluminum and includes an interior pressure relief system for added functionality. Available in anodized Sinister Gray, this cap is rated for 15 PSI and features an etched Sinister Diesel logo.

Fitment

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Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.

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Specifications

BrandSinister Diesel
Part NumberS004 SD-6.6DC01-GRY

Buy with Confidence

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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