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SKU #: WCF-WCF100113-GW
MPN #: WCF100113-GW
Wehrli Custom Fab AAM 11.5" Rear Differential Cover 01-19 GM 6.6L Duramax | 03-18 Ram 5.9/6.7L Cummins
Description
If you lifted your truck you might have found it exposed a massive issue. Your ugly rear axle and differential is now exposed for the world to see! Get a rear differential cover that upgrades the strength, durability, and style of your rear axle along with a fresh cool look with the Wehrli Custom Fabrication AAM 11.5" Rear Differential Cover, designed for Duramax and Cummins-powered heavy-duty trucks. Built from high-quality fabricated aluminum, this cover is engineered to handle the demands of towing, off-road use, and high-performance applications while improving heat dissipation and long-term reliability. Choose from a variety of colors to customize your look!
NOTE: While some colors are kept in stock, other colors will take an extra 10-15 business day delay in powder coating.
Heavy-Duty Protection for Your Rear Axle
Your differential is one of the most critical components in your drivetrain and one of the most vulnerable. This WCFab differential cover replaces the thin factory unit with a robust, precision-built aluminum assembly that provides superior protection against impacts, debris, and extreme conditions.
Precision Fabricated Aluminum Construction
Each cover is laser cut, CNC bent, and fully TIG welded for maximum strength and a perfect fit. The aluminum construction not only adds durability but also helps dissipate heat more efficiently than stock covers, keeping your gear oil cooler under load.
Designed for Work, Towing & Performance
Whether you're hauling heavy loads, towing, or running larger tires, this differential cover helps maintain optimal gear oil temperatures and protects internal components. It’s a must-have upgrade for diesel truck owners who rely on their trucks for both work and performance driving.
Upgrade Your Rear End with Confidence
If you’re looking to protect your investment and improve the performance of your drivetrain, this AAM 11.5" Rear Differential Cover is a proven upgrade. Built to handle real-world abuse while adding a bold, custom appearance, it’s the perfect addition to any Duramax or Cummins build.
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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
You pay for the bid from your preferred shop. The full amount is shown before you confirm — installers cannot add charges without your written consent. Payments are processed securely by Stripe.
Your privacy
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 & amp; BENEFITS
- Fabricated aluminum construction for strength and heat dissipation
- Direct replacement for AAM 11.5" rear axle housings
- Includes fill plug for easy servicing
- Stainless steel mounting hardware included
- Available in multiple custom powder coat finishes
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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