SPOOLOGIC 3in Turbo Downpipe

The SPOOLOGIC SL-520-020 3-Inch Turbo Downpipe upgrades the exhaust path on 2001–2004 Chevrolet Silverado and GMC Sierra pickups equipped with the 6.6L Duramax LB7 and the matching Federal-emissions turbo outlet. Mandrel-bent 3-inch tubing replaces the restrictive factory passage, while preinstalled heat wrap helps limit radiant heat in the engine compartment. The black-finished pipe includes a replacement turbo-to-downpipe gasket for a secure seal at the upper flange.

Features

• 3-inch mandrel-bent tubing provides a smooth exhaust flow path
• Designed to reduce restriction after the turbocharger
• Preinstalled heat wrap helps limit radiant heat transfer
• Welded upper mounting flange and lower clamp-style connection
• Black exterior finish
• Replacement upper flange gasket included

Performance Benefits

The downpipe carries exhaust away from the turbocharger. Its 3-inch mandrel-bent tubing provides a smoother flow path than the flattened, restrictive sections of the factory pipe, helping reduce restriction after the turbine and support throttle response under load. Preinstalled heat wrap helps limit radiant heat transfer to nearby wiring, hoses and other components. Actual changes in performance and exhaust gas temperature depend on the complete exhaust system, engine condition and operating load.

What’s Included

• (1) 3-inch turbo downpipe — SL-520-020
• (1) Heat wrap — preinstalled
• Heat-wrap retaining clamps — preinstalled
• (1) Turbo Downpipe Gasket — SL-310-033

Common Downpipe Leak Symptoms

• Soot around the turbo outlet, downpipe flanges or pipe joints
• Ticking or hissing that becomes more noticeable under load
• Visible cracks, damaged sealing surfaces or severe corrosion
• Rattling caused by a loose mounting bracket or contact with nearby components

Inspect the downpipe, connections and supports to confirm the source of the problem. These symptoms can also come from other exhaust components.

Installation Notes

Compare the turbo outlet flange and lower exhaust connection with the replacement pipe before installation. Clean and inspect the mating surfaces, install the new upper gasket, and check the existing exhaust clamp and fasteners for damage. Align both ends before final tightening, maintain clearance from wiring and hoses, and follow the applicable service torque specifications. Check for exhaust leaks after startup and again after the system has cooled.

Fitment

• 2001–2004 Chevrolet Silverado GMC Sierra 2500 3500 — 6.6L Duramax LB7 with the matching Federal-emissions turbo outlet configuration

⚠️ Does not fit the 2002–2004 California-emissions LB7 turbo outlet configuration. For 2004 trucks, confirm the engine is an LB7; the later LLY uses SL-520-021. Match the installed flange configuration before ordering.

OEM Cross-References

• Turbo downpipe — GM: 97223168 / 97350391
• Turbo-to-downpipe gasket — GM: 97192619

OEM numbers are provided for identification only. This product contains SPOOLOGIC replacement parts.

⚠️ Not for Sale in California

This product is not CARB approved and is not legal for sale or use in California.

1-Year Limited Warranty

Every SPOOLOGIC turbo downpipe is covered by a 1-Year Limited Warranty against defects in materials and workmanship from the date of purchase. Warranty coverage requires that the downpipe first be shipped back to SPOOLOGIC for inspection. If SPOOLOGIC determines the failure was caused by a defect in materials or workmanship, the downpipe will be repaired or replaced at SPOOLOGIC’s discretion. Warranty does not cover damage from improper installation, over-torqued or mis-torqued flange hardware, cracked flanges from improper install sequence, damage from cutting, welding, or modification, heat wrap discoloration or degradation, EGTs beyond the downpipe’s rated operating range, tuning or fueling that exceeds safe exhaust gas temperatures, corrosion from road salt or contaminated environments, use outside the listed fitment, cosmetic wear, or normal heat cycling marks. Warranty does not cover labor, shipping, towing, downtime, gaskets, hardware, or any other costs outside the downpipe itself.