UMI Performance · New
UMI Performance 78-96 GM B-Body Adjustable Upper Control Arms- Roto-Joint
MPN 3628-B · Store SKU umi3628-B
Supplier stock checked 11/7/2026, 6:56:37 AM UTC. Adding a part does not reserve it.
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Product details
UMI’s Roto-Joint adjustable rear upper control arms are a reliable upgrade for your street or pro-touring car. These upper control arms are suitable for various driving conditions, whether it be on the street, strip, or carving corners. The premium spherical joint minimizes suspension deflection for improved handling, easier pinion angle tuning, and reduced wheel hop. The on-car adjustable design allows for easy adjustments while the control arms remain securely bolted to the vehicle. The heavy-duty construction of these control arms, featuring ¼” thick CNC laser cut mounting pads and a combination of TIG and MIG welding, ensures strength and durability. The UMI designed Roto-Joints and chromoly adjuster provide ultimate performance. These bolt-in replacements are designed to fit all rear end housings and can be installed in 1-2 hours. Upgrade your vehicle with UMI’s ultimate control arms and experience improved launch and handling capabilities. UMI’s Roto-Joint adjustable rear upper control arms improve handling, reduce wheel hop, and simplify pinion angle tuning. Built with CNC-cut pads, TIG/MIG welds, and chromoly adjusters, they install in 1–2 hours for street or track use. UMI Roto-Joint uppers boost handling, cut wheel hop, and allow easy tuning.
Manufacturer fitment & guides
Check 3628-B against the manufacturer’s application information below.
Part-specific notes
- California Proposition 65: Y