UMI Performance 78-96 GM B-Body Boxed Lower Control Arms- Poly/Roto-Joint

UMI's boxed lower control arms utilize Roto-Joint technology for a bind-free performance and comfortable ride quality. The control arms are fabricated from 0.120” wall thickness rectangular tubing, with CNC machined bushing holders and MIG welded end caps for durability. The sway bar provisions are reinforced with a steel sleeve for added strength. The delrin lined Roto-Joints eliminate flex and deflection for improved traction and reduced wheel hop. The Roto-Joint design offers 28 degrees of total movement, allowing for smooth operation and precision handling. The delrin race absorbs shock and road noise for a quiet ride. This control arm set features polyurethane bushings on one end and UMI’s swivel Roto-Joint on the other, making it ideal for street performance. The Roto-Joint technology allows for unrestricted movement throughout the suspension, preventing bind and improving traction. The durable construction of the Roto-Joint ensures wear resistance and longevity. The UMI Roto-Joint is adjustable and rebuildable for long-term use. To adjust and disassemble the Roto-Joint, a spanner wrench is included for maintenance purposes.

Additional Information

UMI boxed lower control arms use Roto-Joint tech with 28° movement, reducing wheel hop and improving traction. Made from 0.120" DOM tubing with CNC mounts, delrin-lined joints, and reinforced sway bar provisions. Adjustable and rebuildable.

• 100% rebuildable
• 3” x 1-1/2” x 1/8” rectangular steel tubing construction
• CNC machined for accurate tolerances
• Delrin bushing material for high resistance against wear
• Durable powder coat finish
• High Quality greaseable polyurethane bushings
• MIG and TIG welded for superior strength
• Reinforced sway bar holes
• Roto-Joint allows 28 degrees of total rotation and unrestricted movement
• Roto-Joint features 4140 chrome moly, hard chrome plated spherical ball
• Shipped fully assembled and ready to install
• Spanner wrench for adjusting and disassembling Roto-Joints
• Spherical Roto-Joints installed
• Uses OEM hardware

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Product Downloads

#	Document Type	Download
1.	Installation Instructions

Installation guides, warranty details, and other supporting documents are provided by the supplier. In some cases, these files may originate from regions outside your locale, meaning instructions, warranty procedures, and images may not fully align with your specific vehicle or region (e.g., LHD vs. RHD differences, return policies, etc.). If you need clarification, please contact a StreetFX support agent.

Reference Information