2020-2026 L5P Duramax 3.5" Passenger (Cold) Side Intercooler Pipe Kit

A cold side pipe that holds boost

Wehrli replaces the failure-prone factory L5P passenger (cold) side pipe with a larger one-piece 3.5 in. pipe in 14 ga aluminum.

It replaces the factory rubber-and-plastic design. A black anodized billet adapter with twin O-rings, a silicone boot and stainless T-bolt clamps seal the upper end, a CNC-machined flange with twin O-rings seals the intercooler end, and a threaded bung takes the factory intake temperature sensor.

Wehrli says the better flow between the turbo and engine improves efficiency, throttle response and spool. It fits stock trucks with no other changes or tuning and installs with basic hand tools.

Who it's for

L5P owners, stock or modified, who are tired of blown cold side boots and boost leaks.

Key specs (per Wehrli)

What's included

• 3.5 in. cold side intercooler pipe
• Billet adapter with O-rings
• Silicone boot and stainless T-bolt clamps; powder-coated finish

Fitment notes

• Fits 2020-2026 Chevrolet Silverado / GMC Sierra 2500 HD and 3500 HD with the 6.6L L5P Duramax.
• Replaces GM part numbers 23420958 and 84682179.
• California: Wehrli does not ship this part to California.

Professional install available at Powertech Diesel, Idaho Falls — call 208-542-7793.