Throttle Body Spacer for Jeep Grand Cherokee (1999-2004) 4.0L

Precision Billet Throttle Body Spacer for 1999-2004 Jeep Grand Cherokee

What it Does: Increases intake plenum volume and stabilizes inlet air velocity between the throttle body and manifold to improve low-end torque and throttle response on 4.0L engines.

The Stock Grand Cherokee Intake Velocity Restriction

The factory intake assembly on the 4.0L WJ places the throttle body in direct, blunt contact with the cast intake manifold plenum. This compact runner geometry causes localized turbulence and boundary-layer shear at immediate tip-in, disrupting smooth volumetric filling at low-to-mid RPM operating ranges. In low-speed trail crawls or loaded towing scenarios, this abrupt transition results in sluggish engine response and delayed low-end torque development.

The Engineering Solution

CNC-machined from solid 6061-T6 billet aluminum, this spacer provides structural rigidity and resists thermal deformation under severe engine bay heat soak. The extended bore geometry lengthens the intake tract to smooth incoming airflow vectors directly into the manifold runners, promoting uniform air mass distribution. An anodized surface finish prevents galvanic corrosion, while the included 304 stainless steel extended hardware maintains uniform clamping torque across the mating gasket to prevent vacuum leaks.

Technical Specifications

Compatibility

• 1999-2004 Jeep Grand Cherokee WJ (4.0L Inline-6 Engine)
• Fits Laredo, Limited, Sport, Special Edition, and Columbia Edition trims

The Jeep Trail-Ready Standard

Engineered to withstand prolonged thermal cycling, chassis vibration, and severe off-camber trail stress, this solid-billet spacer delivers reliable low-RPM throttle modulation without cracking or risking manifold air leaks in off-road environments.