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Note: This item is build to order
Note: The build time is approximately 60 days for this part
Note: This product is NOT for sale in California
Sinister Diesel's Billet Valve covers for the 2004.5-2010 Duramax will help clean up the engine bay, and add a little more clearance for custom turbo or fuel upgrades. These are fully CNC machined, then they are anodized in the Sinister Blue color for good looks and a long life.
These retain the factory Fuel Filter housing as well as the Radiator hose hard line.
These DO NOT have any other provisions for wiring harnesses or accessories. These will work on a stock truck with the wiring harness tied back.
Upper valve cover includes new gaskets, and will retain factory hardware, or will work with aftermarket hardware like the ARP dress up kit.
You may return most new, unopened items within 30 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).
You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).
If you need to return an item, please Contact Us with your order number and details about the product you would like to return. We will respond quickly with instructions for how to return items from your order.
We can ship to virtually any address in the world. Note that there are restrictions on some products, and some products cannot be shipped to international destinations.
When you place an order, we will estimate shipping and delivery dates for you based on the availability of your items and the shipping options you choose. Depending on the shipping provider you choose, shipping date estimates may appear on the shipping quotes page.
Please also note that the shipping rates for many items we sell are weight-based. The weight of any such item can be found on its detail page. To reflect the policies of the shipping companies we use, all weights will be rounded up to the next full pound.
Coops Custom offers custom products and custom bundles with certain products, if you have a major project and you need more than one part please contact us at 800-214-6218.
| Fender Flares: | Available in color match colors. |
| Colored Matched Bud Shields: | Most of our AVS bug shield are avialble in color match. |
| Power Combos: | We offer bundles of tuners, exhausts and air intakes. |
| wheels and Tires: | Coops offers mounted and balanced Wheel and Tire Combos. |
Coops Customs General Aftermarket Auto Part FAQ.
