Wehrli GMC/Chevrolet LLY/LBZ/LMM Duramax 6.6L w S400 Single Turbo 3in Down Pipe - Black

If you're upgrading your LLY, LBZ, or LMM Duramax 6.6L engine with an S400 single turbocharger, you'll need a proper down pipe to connect it to your exhaust system. This 3-inch down pipe from Wehrli Custom Fabrication is built to handle the demands of a larger turbo setup.

This down pipe is designed to mate with the S400 turbo's 4.6-inch diameter flat exhaust outlet flange, often called a Marmon flange. It uses a V-band clamp to connect to your existing exhaust system's V-band flange, which makes installation more straightforward than some other methods. The pipe itself is finished with a high-temperature coating to help resist heat and corrosion, and it's made in the USA. Keep in mind that this down pipe requires a T4 pedestal that is between 5.5 and 6.5 inches tall to position the turbo correctly.

This specific part is for the LLY, LBZ, and LMM Duramax engines. If you have an LB7 Duramax, you'll need a different part number (WCF100878). Please note that this part is not CARB approved and cannot be shipped to California.