Gibson GP400S Stainless Steel Header for 91-99 Jeep Wrangler YJ, TJ & (Grand) Cherokee XJ, ZJ, WJ with 4.0L I-6 Gasoline Engine

Enhance the performance and reliability of Jeep's legendary inline-six engine with the Gibson Stainless Steel Header. Designed specifically for 1991–1999 Jeep Wrangler YJ and TJ, Cherokee XJ, Grand Cherokee ZJ, and Grand Cherokee WJ models equipped with the 4.0L gasoline engine, this performance header replaces the restrictive factory exhaust manifold with a high-flow tubular design engineered to improve exhaust efficiency and engine breathing.

Constructed from premium stainless steel, the GP400S delivers outstanding resistance to corrosion, rust, and the extreme temperatures generated by the exhaust system. Its tuned runner design promotes improved exhaust scavenging and reduced backpressure, helping support gains in horsepower, torque, and throttle response across the RPM range. Built for long-term durability and dependable performance, this header also serves as an excellent replacement for aging or cracked factory manifolds. Whether restoring lost performance or upgrading for improved engine efficiency, the Gibson Stainless Steel Header delivers the quality craftsmanship and proven engineering Jeep enthusiasts expect.

Installation Notes

Installation Difficulty:

Level 3Advanced

Installation Time: 3-6 hours

Parts Included

• Header
• Gaskets
• Hardware

Warranty

Limited Lifetime Warranty.