Wehrli 2020-2024 Duramax L5P Stage 3 High Flow Bundle Kit WCFab Grey

Addressing intake, intercooler, and exhaust restrictions in a single kit, this Wehrli Custom Fab Stage 3 High Flow Bundle handles the full airflow path on the 2020-2025 Duramax L5P. It fits both Chevrolet Silverado and GMC Sierra 2500 HD and 3500 HD trucks, and comes finished in WCFab Grey powder coat for a clean, understated look in the engine bay.

Cold air enters through the hood ram air duct and inner fender via a 4-inch aluminum intake pipe and enclosed air box with a dry filter and Outerwears hydrophobic pre-filter cover. The oversized intake horn -- over an inch larger than stock -- feeds the turbo with more air volume, and the Y-bridge connection uses a silicone boot with stainless T-bolt clamp instead of the factory clip ring for a tighter, more reliable seal under boost pressure.

The intercooler pipes replace two known problem areas in the factory system. On the driver side, the one-piece 3-inch tube eliminates the factory resonator and middle boot joint. The 3.5-inch passenger-side pipe swaps out the factory's plastic and rubber assembly for a 14-gauge aluminum tube sealed with a CNC machined flange and double O-ring. Both pipes use mandrel bends and stainless T-bolt clamps at every connection.

Rounding out the Stage 3 package, the 3.5-inch down pipe replaces the crushed factory exhaust piece with a ceramic coated and heat-wrapped tube that flows noticeably better. It bolts to the DOC outlet flange and connects to the OEM exhaust system front pipe using the factory 4-bolt connection, retaining all sensor bungs. The whole kit goes on with basic hand tools, no tuning or cutting needed, and it retains every factory connection point and sensor location.