GMC Sierra Performance Exhaust - aFe - Twisted Steel Up-Pipe - `01-`04 is a direct-fit Twisted Steel header up-pipe for 2001–2004 GM 6.6L LB7 V8 diesel trucks. It provides a durable, serviceable replacement intended to improve exhaust flow and long-term reliability compared with worn OEM pieces.

Built from 2" mandrel-bent 304 stainless steel with a 0.120" wall, this aFe Twisted Steel up-pipe resists corrosion and maintains shape under heat and vibration. The unit uses heavy-duty 2" inner-liner flex tubing to help absorb movement and reduce stress on connections. Precision 3/8" thick laser-cut flanges supply a full 360° sealing surface to minimize leaks when installed correctly. This up-pipe is suited for enthusiasts who want a robust OEM-replacement part that supports further exhaust upgrades.

Features

• 2" mandrel-bent 304 stainless steel tubing with 0.120" wall
• Heavy-duty 2" flex tubes with internal inner liner
• 3/8" thick laser-cut flanges for a 360° sealing surface
• Direct fit for 2001–2004 GM 6.6L LB7 V8 diesel trucks
• Twisted Steel header up-pipe design for improved flow and durability

If you have questions about fitment or installation, call us directly — we’re happy to help: 512-982-9393 (TX) or 562-981-6800 (CA). We have two service locations in Austin, Texas and the Los Angeles, California area where we offer installation and customization services.

If you are considering purchasing multiple items, please contact us for potential shipping discounts. We install on premises at both locations.

CA Residents: WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov