American Racing Headers GM Truck 6.0L 1999-2006 Long System

American Racing Headers GM Truck 6.0L 1999–2006 Long System

ARH long tube headers long system for the 1999-2006 Chevy/GM Truck/SUV 6.0L features 304 stainless steel 1 3/4" primaries, 3" merge collectors, and y-pipe along with all the necessary hardware and gaskets for a bolt-on installation.

The 1999-2006 Chevy/GM Truck/SUV 6.0L American Racing Headers long systems were designed to bolt-on to your factory axle-back or any aftermarket axle-back. Some modification may be required. The American Racing headers require a crossover y-pipe assembly and they are offered with or without converters. Using the catted crossover pipes cause very little restriction and they help to control emissions.

System Specifications

• Material: 100% 304 stainless steel
• Primary Tubes: 1 3/4"
• Collectors: 3" merge collectors with scavenger spikes
• Connection: Long system with crossover Y-pipe (catted or off-road options)
• Flanges: 3/8" thick, laser-cut for a warp-free seal
• Inlets: Hand-ported, TIG-welded
• Hardware: Includes clamps, hardware, and gaskets for bolt-on installation
• Cats (catted systems): 200-cell metallic substrate catalytic converters
• Origin: 100% Made in the USA – never outsourced

Vehicle Fitment & Compatibility

• Years: 1999–2006 (GMT800 platform)
• Engine: GM/Chevy 6.0L V8 (e.g., LQ4/LQ9)
• Platforms: Silverado/Sierra 1500HD/2500/2500HD, Suburban/Yukon XL 2500, Avalanche 2500, Escalade/Denali 6.0L, and other GM full-size Truck/SUV applications with 6.0L*
• Axle-Back Compatibility: Designed to bolt to factory or aftermarket axle-back systems (some modification may be required)

*Fitment can vary based on drivetrain (2WD/4WD), wheelbase, and chassis options. Verify configuration before purchase.

Performance & Installation Notes

Optimized primary routing, merge collectors with scavenger spikes, and a free-flowing Y-pipe deliver excellent exhaust scavenging, improved throttle response, and gains throughout the powerband. The catted Y-pipe option uses high-durability 200-cell metallic catalysts that minimize restriction while helping manage emissions. A professional installation is recommended; ECU recalibration may be beneficial to maximize performance and address potential CELs when changing catalytic configuration.

Key Product Features

• 100% Made in the USA - Never Outsourced
• Made entirely of 304 stainless steel
• 3/8" thick laser-cut flanges for a warp-free seal
• Hand-ported TIG welded inlets
• Optimized primary tube routing for superior fit and performance
• Merge collectors with scavenger spikes
• Catted systems feature 200 cell metallic substrate catalytic converters for extreme durability

What’s Included

• Left & right 304SS long-tube headers (1 3/4" primaries)
• 3" merge collectors
• Cross-over Y-pipe (choose catted or off-road)
• Installation hardware & multi-layer gaskets
• O2 sensor provisions

Emissions Notice

Intended for racing/competition or off-road use where applicable. Check local and state laws regarding emissions compliance and catalytic converter requirements.