UMI Performance · New
UMI Performance 78-88 G-Body Rear Lower Control Arms- Roto-Joint/Roto-Joint
MPN 3040-R · Store SKU umi3040-R
Supplier stock checked 11/7/2026, 6:00:02 AM UTC. Adding a part does not reserve it.
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Product details
UMI's tubular lower control arms utilize our Roto-Joint technology for a bind free performance and quiet comfortable ride quality. The Roto-Joint design is a pivot ball lined with a greaseable delrin race designed to offer 28 degrees of total unrestricted movement, more than adequate for a bind free, low friction operation. The Roto-Joint design improves performance over the factory rubber and aftermarket polyurethane bushings by allowing the suspension to articulate correctly, and provide precision handling. The installed UMI Roto-Joint allows rear end free movement when high handling, auto cross or road race is a concern while still being a 100% streetable setup. The installed delrin race, which lines the spherical ball, absorbs shock and road noise for a quiet and smooth operation on any street or track driven vehicle. This control arm set features Roto-Joints on both sides of the control arms. This is designed for maximum performance and suspension travel. Both control arms feature the correct provisions for adding a stock or aftermarket sway bar. Sway bar holes are reinforced with a 0.120” wall thickness steel sleeve that TIG welded and sanded into place. All Roto-Joints are greaseable and low maintenance making an excellent street setup for your cruiser or race car! 3040 - 1978-1988 G-Body Rear Lower Control Arms- Roto-Joint/Roto-Joint Constructed of 1.500” x 0.120” DOM mild steel tubing Shipped fully assembled and ready to install Brilliant and durable powder coat finish Spherical Roto-Joints installed Reinforced sway bar holes Uses OEM hardware Fully TIG welded Features:
Manufacturer fitment & guides
Check 3040-R against the manufacturer’s application information below.
Part-specific notes
- California Proposition 65: Y