The SPOOLOGIC Heavy Duty 304SS High-Flow Bellowed Up-Pipes SL-510-022 replace the leak-prone factory up-pipes on 2004.5-2005 Chevrolet Silverado GMC Sierra 2500 3500 6.6L Duramax LLY with mandrel-bent 304 stainless steel pipes that hold up under high EGT and high-mileage thermal cycling.

Mandrel-bent for maximum exhaust flow with integrated multi-layer bellows that absorb thermal expansion instead of cracking the joints. Welded flanges, direct-fit to the factory manifolds and turbo collector — no modifications required.

Common 6.6L LLY Duramax Up-Pipe Failure Symptoms

If your 6.6L LLY Duramax truck is showing any of these symptoms, the factory up-pipes are most likely the cause:

• Exhaust leak between manifold and turbo — ticking or "exhaust tap" on cold start, hissing under boost
• Loss of boost and reduced power — leaking up-pipes bleed off pre-turbine exhaust pressure, slowing spool and dropping peak boost
• Black sooting on the up-pipe joints — visible carbon trails at the manifold or turbo flanges
• Excess EGT and reduced fuel economy — ECM compensates for lost boost with more fuel, raising EGTs

Why 304SS Bellowed Up-Pipes Outlast OEM

Factory up-pipes use thin-wall tubing with simple slip joints that crack and leak after a few thermal cycles. SPOOLOGIC pipes are mandrel-bent 304 stainless steel with multi-layer bellows that flex with heat expansion. Welded flanges, thicker wall, longer service life.

What's Included

• 304SS bellowed up-pipes (one with a 2-bolt branch flange)
• triangular 3-hole up-pipe gaskets (flat)
• round 3-hole up-pipe gaskets (flat)
• oval 2-hole gasket (flat)
• silver flange bolts
• black bolts

Features

• Mandrel-bent 304 stainless steel construction — corrosion resistant, heat tolerant, outlasts factory mild-steel pipes
• Multi-layer bellowed expansion joints absorb thermal expansion — no cracking at the sealing surface
• Flat-flange design with new gaskets — permanently fixes the OEM crush-donut / slip-joint leak point
• TIG-welded flanges for full-penetration, leak-free joints
• Application-specific — direct-fit to the listed manifolds and turbo collector, no modifications required
• Includes gaskets and hardware for a complete installation
• Backed by a 1-Year SPOOLOGIC Limited Warranty

Turbo Application: GT3788VA

Fits 2004.5-2005 6.6L Duramax LLY

• 2004.5 – 2005 Chevrolet Silverado GMC Sierra 2500 / 3500 6.6L Duramax LLY

Replaces Factory OEM Part Numbers

• 11611132
• 97188685
• 97192618
• 97303648
• 97328807
• 97354615

Emissions Notice: Not CARB approved. Not legal for sale or use in the state of California.

1-Year Limited Warranty

Every SPOOLOGIC heavy-duty 304SS bellowed up-pipe kit is covered by a 1-Year Limited Warranty against defects in materials and workmanship from the date of purchase. Warranty coverage requires that the kit first be shipped back to SPOOLOGIC for inspection. If SPOOLOGIC determines the failure was caused by a defect in materials or workmanship, the affected component will be replaced at SPOOLOGIC's discretion. Warranty does not cover damage from improper installation, over-torqued flange bolts, use outside the listed fitment, cracks caused by seized OEM hardware, corrosion from prolonged salt or coastal exposure once the raw 304SS finish is chipped or gouged, damage from a failing turbo, cosmetic wear, or normal darkening of the raw 304SS finish under heat. Warranty does not cover labor, shipping, towing, downtime, gaskets consumed on subsequent removal, or any other costs outside the up-pipe kit itself.