FREE 1 to 3-Day Delivery on Orders $149+ Details

Memorial Day Sale - Up to 50% Off! Shop Now >

Find for your Sierra 3500

Sinister Diesel Coolant Block-Off Plate; Blue (14-26 6.6L Duramax Sierra 3500 HD)Find parts that fit my vehicle

Item SHG66589
Product Image
Our Price

$69.99

Military, Medical & First Responders $3.50 Available in AT Cash Rewards.
Confirm Eligibility

CONFIRM THIS FITS YOUR VEHICLE!

Select a different vehicle Help?
Update or Change Vehicle
Add to Cart
Save for later
    Create a list
    Add to New List

    Saved - View your saved items

    We're sorry. We couldn't save this product at this time.

    or use

    Shop Owners Save More! Sign up for our dealer program
    Join For FREE
    Loading Indicator

      Product Information

      Features, Description, Q&A

      Features

        _x000D_
      • OEM Block-Off Plate Uses a Gasket That May Leak Over Time
        • _x000D_
      • Sinister Diesel Billet Block-Off Plate Is Thicker and Features a Durable O-Ring Seal
        • _x000D_
      • O-Ring Designed for Maximum Longevity
        • _x000D_
      • Anodized Sinister Blue Finish
        • _x000D_
      • CNC Machined from T6-6061 Billet Aluminum
        • _x000D_
      • Etched Sinister Diesel Logo
        • _x000D_
      • Replacement for Failure-Prone OEM Plate with Gasket
        • _x000D_
      • Fits 2014-2026 6.6L Duramax Sierra 3500 HD
        • _x000D_

      Description

      Premium Coolant Seal. The Sinister Diesel Coolant Block-Off Plate Blue is an essential upgrade to the factory coolant block-off plate, eliminating leaks commonly caused by the original gasket design. It enhances the reliability of the coolant reservoir system, extending the life of engine components and ensuring consistent coolant containment under all operating conditions.

      _x000D__x000D_

      Construction and Appearance. This block-off plate is precision CNC machined from T6-6061 billet aluminum and finished with an anodized Sinister Blue coating, providing a durable and visually appealing surface. The plate features an etched Sinister Diesel logo for brand authenticity, and the included O-ring ensures a tight, leak-resistant seal for long-term durability.

      _x000D__x000D_

      Installation. Installation is straightforward and requires no drilling or modifications to existing vehicle components. It is designed as a direct replacement part, allowing for quick and easy installation by professionals or experienced enthusiasts.

      _x000D__x000D_

      Warranty. The product includes a standard warranty covering manufacturer defects and workmanship for a specified period from the date of purchase.

      _x000D__x000D_

      Application. Specifically engineered to fit the 2014-2026 6.6L Duramax Sierra 3500 HD, this block-off plate addresses known OEM gasket failures and is not compatible with other vehicle models or engine configurations.

      Sinister Diesel SD-CBO-DMAX-01

      CA Residents: WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

      Questions & Answers

      No questions about this product yet. Ask the First Question

      Will It Fit My Sierra 3500

      • 6.6L V8 Duramax - 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26