UMI Performance 4038-B Rear Lower Control Arms with Roto-Joint Technology

UMI Performance's 4038-B rear lower control arms combine advanced Roto-Joint technology with precision engineering to deliver bind-free performance and exceptional ride quality. These tubular control arms are constructed from 1.500" x 0.120" DOM mild steel tubing and feature full TIG welding throughout for maximum strength and durability.

Roto-Joint Technology:

The innovative Roto-Joint design features a pivot ball lined with a greaseable Delrin race, providing 28 degrees of total unrestricted movement. This allows the suspension to articulate correctly while eliminating binding and friction that plague factory rubber and aftermarket polyurethane bushings. The Delrin race absorbs shock and road noise for quiet operation on both street and track applications.

Hybrid Bushing Design:

This control arm set features a hybrid configuration optimized for street performance enthusiasts. Energy Suspension greaseable polyurethane bushings mount to the chassis side to absorb road noise and shock before it enters the passenger compartment, while UMI's spherical Roto-Joints attach to the rear axle side for precision handling and free rear end movement during aggressive driving.

Key Features:

• Constructed from 1.500" x 0.120" DOM mild steel tubing with full TIG welding
• Spherical Roto-Joints pre-installed with 28 degrees of unrestricted movement
• Energy Suspension greaseable polyurethane bushings on chassis end
• Reinforced sway bar mounting holes with TIG-welded 0.120" wall steel sleeves
• Low-deflection Delrin race for improved traction and handling
• Uses OEM hardware for direct installation
• Durable powder coat finish in brilliant color
• Ships fully assembled and ready to install
• All bushing ends and Roto-Joints are greaseable for low maintenance
• 100% streetable setup suitable for daily driving, autocross, and road racing

These control arms are designed for both street performance and track applications, providing the precision handling needed for competitive driving while maintaining comfort for daily use. The greaseable design ensures long-lasting performance with minimal maintenance.