DIAMOND EYE 321055 TURBO DOWNPIPE 3 INCH INLET/OUTLET FOR 01–04 SILVERADO/SIERRA 2500/3500 6.6L LB7 PERFORMANCE SERIES

DIAMOND EYE 321055 is a 3.0" aluminized steel turbo direct downpipe for 2001–early 2004 GM 6.6L LB7 Duramax. It replaces the restrictive OE unit to improve flow, reduce drive pressure, and help lower EGTs. Features include a CNC-machined, pocketed turbo flange and thermal wrap for heat control.

Features

• 3.0" mandrel-bent aluminized steel tubing
• CNC-machined & pocketed turbo outlet flange for precise fit
• Thermo wrap to help reduce under-hood heat and EGTs
• Direct turbo-to-front-pipe connection (turbo direct pipe)

FAQ: IS THIS 50-STATE / CARB LEGAL?

This performance downpipe is not legal for sale or use in California on pollution-controlled vehicles. For off-road / federal-emissions use only where permitted.

FAQ: DOES IT REQUIRE MODS?

On some trucks, a minor clearance tweak/relocation of the transmission dipstick tube may be required. Test-fit before final tightening.

FAQ: WHAT DOES IT FIT?

Designed for 2001–early 2004 Chevrolet Silverado / GMC Sierra 2500/3500 HD with the 6.6L LB7 Duramax (all cab & bed lengths). Will not fit LLY/LBZ/LMM/L5P.

Fitment Details

• Platform: 2001–early 2004 GM 2500/3500 HD
• Engine: 6.6L Duramax LB7
• Connection: Turbo outlet to front/down pipe (direct)
• Notes: Federal-emissions only; minor dipstick-tube adjustment may be needed on some vehicles

Cross-Reference / Related Diamond Eye Parts (on CPP Diesel)

• K4110A-RP — 01–05 Duramax 4" Cat-Back, No Muffler (Aluminized)
• K4110S-RP — 01–05 Duramax 4" Cat-Back, No Muffler (Stainless)
• 321045 — 4" Exhaust Flange (Aluminized) for 01–07.5 GM 2500/3500

Specifications