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SKU #: WCF-WCF100025
MPN #: WCF100025
Wehrli Custom Fab Coolant Plug 1.1" Bore 11-19 GM 6.6L Duramax
Description
The WCFab Duramax Coolant Plug is a simple and effective solution for sealing unused coolant ports on your Duramax diesel engine. Precision CNC-machined from billet aluminum and finished with a durable black anodized coating, this plug provides a clean, leak-free seal while adding a professional look to your engine bay.
Designed for Duramax engine covers with a 1.1-inch bore, this plug installs easily and includes a high-temperature silicone O-ring to ensure a reliable seal under extreme engine heat and pressure. Whether you're completing a custom engine build, cleaning up unused ports, or finishing an engine swap project, this coolant plug offers a durable and professional solution.
Durable Cooling System Solution
The Duramax cooling system can require port block-offs when performing engine
modifications, aftermarket turbo installations, or custom fabrication work.
The WCFab coolant plug is engineered to handle the demanding
environment of a diesel engine bay while maintaining a reliable seal against coolant leaks.
Its billet aluminum construction provides superior durability compared to plastic plugs, while the anodized coating helps prevent corrosion and wear over time.
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About WrenchConnected
WrenchConnected is an independent installation marketplace operating in partnership with Diesel Power Products.
How it works
After checkout, we route your vehicle info and part SKU to verified installation shops near you. Local installers review the job and submit competitive bids; you pick the shop you want based on price, reviews, and availability. Your name and email stay private until you select an installer.
Pricing
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During bidding, shops see only your service ZIP code, vehicle year/make/model, and the part SKU — not your name, email, or address. Only the shop you select receives your contact details after payment. We never sell your personal information.
More detail at wrenchconnected.com.
FEATURES & BENEFIT:
- CNC-machined billet aluminum coolant plug
- Durable black anodized finish for corrosion resistance
- Fits Duramax engine covers with 1.1" bore
- Includes high-temperature silicone O-ring seal
- Provides a secure, leak-free seal for unused coolant ports
- Perfect for engine swaps, custom builds, and cooling system modifications
About Wehrli Custom Fabrication
Born from a garage dream in Sandwich, Illinois, and now headquartered in DeKalb, Illinois, Wehrli Custom Fabrication (WCFab) has earned a formidable reputation in the diesel performance world. From its hands-on beginnings to its expansion into a team of 50-plus skilled builders, WCFab continues to elevate diesel upgrades, even as the brand evolves into fabrication and powder coating excellence.
At its core, Wehrli is dedicated to powering Duramax, Powerstroke, and Cummins trucks with rugged, high-performance parts that meet the real-world demands of hauling, towing, and racing. Every product is proudly Made in the USA, from turbo kits and cold air intakes to heavy-duty Allison transmission builds capable of handling up to 750hp, thoroughly crafted in a climate-controlled clean room.
Whether you’re upping airflow with precision CNC-machined intakes and intake horns, clearing the engine bay with billet block-off plates, or commanding raw transportation power with a 750+hp Allison transmission, Wehrli’s work is synonymous with resilience and peak performance. Products like their L5P Duramax high-flow turbo intake horn boast a 27% increase in flow, proving that function and form can coexist beautifully.
Customer support is a serious affair at WCFab they stand firmly behind their fits and finishes Led by the Wehrli brothers and a crew fueled by diesel passion, the brand’s mission is clear: deliver top-tier craftsmanship, unmatched performance, and relentless customer service.
Wehrli Custom Fabrication—where diesel dreams are forged into reality, in metal you can feel and performance you can trust.
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