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Sinister Diesel  |  SKU: SINSD-6.6DC01-GRY
23% off

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

Sale price USD 9001 Regular price USD 11702

Can I pick up my order or have it installed at your shop?

Absolutely. We offer local pickup on most products and full professional installation at our shop in Washington, MO. Whether you just want to grab your parts or have our techs handle the install, we’ve got you covered. Give us a quick call at636-429-7020or message us to schedule a visit — we’ll make sure the parts are ready when you arrive.

How do I know if this part fits my vehicle?

Unsure if it’ll fit? No problem — that’s what we’re here for. Send us your vehicle’s year, make, and model, and we’ll verify fitment before you order. We can also point you toward compatible upgrades or supporting parts if needed.

What if I need to return a product or it’s defective?

Most unused items can be returned within 30 days in their original packaging. Some products are covered by a manufacturer’s warranty as well. If something arrives damaged or doesn’t meet your expectations, just let us know — we’ll help you get it replaced, refunded, or repaired. (Tracking updates are also emailed automatically once your order ships.)

What's the lead time on custom or fabricated parts?

Many of our parts are built to order — especially fabricated or performance components. These can take additional time to produce before shipping. Lead times vary by manufacturer and demand, but we’ll always keep you updated along the way. If you’re working on a tight schedule, reach out before ordering at636-429-7020and we’ll confirm current availability or estimated ship dates.

Description

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, this cap looks as good as it works!., Features:Cap is rated for 15 PSI, Available in Anodized Sinister 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;Includes:(1) Sinister Diesel Coolant Reservoir Cap.