Gibson 05-06 Chevrolet Avalanche 2500 LS 8.1L 1-3/4in 16 Gauge Performance Header – Stainless

SKU: GP134S | UPC: 677418012422

Gibson 2005-2006 Chevrolet Avalanche 2500 LS 8.1L 1-3/4in 16 Gauge Performance Header – Stainless

Gibson Performance Headers GP134S deliver dyno-tuned power gains in horsepower and torque across low and mid-range RPM for highway speeds on 2004-2006 Chevrolet Avalanche 2500 and compatible GM trucks with 8.1L engines. These 1-3/4 inch 16-gauge stainless steel headers replace factory manifolds directly using the stock crossover pipe for improved engine breathing and lower operating temperatures. Perfect for street, off-road, lowered or lifted vehicles with no welding required and full 50-state street legality.

Key Features

• Dyno-Tuned Design: Engineered for maximum usable horsepower and torque at everyday driving RPMs with proven gains on 8.1L Vortec engines
• Premium Stainless Construction: 16-gauge tubing and 3/8-inch heavy-duty laser-cut port flanges prevent warping, leaks, and ensure long-lasting durability
• Bolt-On Installation: Direct replacement for stock manifolds with OEM-style connections, premium gaskets, and hardware included for hassle-free fit
• Emissions Compliant: Meets EPA and CARB standards for 50-state legality without impacting factory warranty
• Versatile Application: Fits lowered, raised, street, and off-road setups while reducing engine heat for better performance

Product Notes

• Retains factory crossover pipe for simple integration and emissions compliance
• MPN GP134S backed by Gibson Lifetime Limited Warranty
• Special order item ships via standard ground freight

Installation Notes

• Professional installation recommended.
• No welding or modifications needed. bolts directly to factory mid-pipes
• Includes all necessary premium gaskets, hardware, and OEM connections

This Part Fits

Year	Make	Model	Submodel
2004	Chevrolet	Avalanche 2500	Base
2005-2006	Chevrolet	Avalanche 2500	LS
2005-2006	Chevrolet	Avalanche 2500	LT
2004-2005	Chevrolet	Silverado 2500 HD	Base
2004-2005	Chevrolet	Silverado 2500 HD	LS
2004-2005	Chevrolet	Silverado 2500 HD	LT
2004-2005	Chevrolet	Silverado 2500 HD	WT
2004-2005	Chevrolet	Silverado 3500	Base
2004-2005	Chevrolet	Silverado 3500	LS
2004-2005	Chevrolet	Silverado 3500	LT
2004	Chevrolet	Silverado 3500	WT
2004-2005	Chevrolet	Suburban 2500	LS
2004-2005	Chevrolet	Suburban 2500	LT
2004-2005	GMC	Sierra 2500 HD	Base
2004-2005	GMC	Sierra 2500 HD	SLE
2004-2005	GMC	Sierra 2500 HD	SLT
2004-2005	GMC	Sierra 2500 HD	WT
2004-2005	GMC	Sierra 3500	Base
2004-2005	GMC	Sierra 3500	SLE
2004-2005	GMC	Sierra 3500	SLT
2004-2005	GMC	Sierra 3500	WT
2004-2005	GMC	Yukon XL 2500	SLE
2004-2005	GMC	Yukon XL 2500	SLT

Why Choose Gibson?

• Over 30 years of exhaust engineering expertise for GM heavy-duty trucks
• Dyno-tested on real vehicles for verified power gains on 8.1L engines
• Made in USA with lifetime warranty on materials and craftsmanship

Frequently Asked Questions

• Q: Will GP134S fit my 2005 Chevrolet Silverado 2500 HD LS 8.1L?
  A: Yes, confirmed fit for 2004-2005 Silverado 2500 HD Base, LS, LT, WT with 8.1L Vortec. check submodel in fitment table
• Q: What material are these headers made from?
  A: 16-gauge T-304 stainless steel tubing with 1-3/4 inch primaries and 3/8-inch laser-cut flanges for corrosion resistance and strength
• Q: Does installation void my warranty or require tuning?
  A: No impact on factory warranty. bolt-on design uses stock parts, no tune or welding needed, fully emissions legal

Shipping & Handling

• Method: Standard ground freight
• Availability: In stock – ships same or next business day
• Packaging: Oversized box measures 48 x 18 x 12 inches
• Weight: 45 lbs