UMI Performance 305756-3-B Upper & Lower A-Arm Kit for 1978-1988 GM G-Body

The UMI Performance 305756-3-B is a complete upper and lower A-arm kit engineered for maximum front-end performance on 1978–1988 GM G-Body vehicles. Built from USA-made DOM steel tubing, this kit delivers up to 10 degrees of caster potential while maintaining standard track width and wheelbase — making it a true direct bolt-in upgrade over factory suspension geometry.

Key Features:

• Adjustable upper A-arm utilizes precision rod ends for easy alignment and superior friction reduction for quick steering response
• Upper ball joint repositioned rearward to add 5–6 degrees of caster potential for improved steering feel and straight-line stability
• Lower ball joint relocated forward to increase caster by an additional 4–5 degrees
• Taller upper ball joints improve camber gain, optimize roll center, and enhance traction during cornering
• Tall lower ball joint optimizes roll center, camber gain, center of gravity, and lowers ride height by ½"
• UMI Delrin bushings on the lower A-arm provide bind-free operation, improved steering response, and reduced deflection
• Removable double shear lower shock mount allows spring and shock replacement without removing the spindle — ideal for track use
• Double shear swivel sway bar mounts compatible with UMI P/N 3035 and most factory eyelet-style sway bars
• Adjustable aluminum steering stop limits steering lock to protect tires and wheels
• Mount spacing compatible with AFCO, Viking, Ridetech, and many other aftermarket shock/spring combinations
• Available in UMI red or black powder coat finish
• 100% designed, tested, manufactured, and raced in Philipsburg, PA, USA — battle tested on the iconic UMI Green Machine

Performance Note: UMI recommends pairing this kit with the UMI P/N 3060 bump steer kit for optimal front-end performance.

This A-arm kit is a direct bolt-in solution for serious G-Body performance builds, delivering the geometry improvements needed for autocross, road course, and high-performance street driving. Cross-reference: UMI 305756-3.