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Get it between 2025-07-31 to 2025-08-07. Additional 3 business days for provincial shipping.
Made in the USA with limited lifetime warranty
Thick 16GA tubing and 3/8 inch thick flanges
T-304 stainless steel
T-304 stainless steel
CARB approved, 50 state smog legal
Doug Thorley Headers THY-312 4:1 long tube headers deliver the ultimate in performance and gas mileage for your 2001-2011 GM Class A Motorhome. 4:1 long tube headers are designed to replace the factory stock exhaust manifolds with a performance component that results in a serious increase in exhaust flow over stock. That better exhaust flow produces noticable gains in horsepower and torque output, while increasing fuel efficiency. These particular headers are manufactured using heavy duty 16GA stainless steel tubing, and super flat 3/8 inch head flanges. APPLICATION SPECIFICS: 2001-2011 GM Class A Motorhome, 8.1L, with EGR fittings.