Designed, engineered, tested, and assembled in Colorado, SPC Performance adjustable upper control arms are loaded with features. Improve suspension travel, handling, and tire wear while centering the tire in the wheel well for maximum clearance needed for oversized tires. Now equipped with maintenance-free ball joints and free-pivoting xAxis™ sealed flex joints in bonded rubber sleeves, for correction of alignment angles and restoration of factory ride quality. A Forged steel design provides the strength and durability needed for the most demanding environments. SPC adjustable control arms have improved clearance to get around the sp ring bucket and a full 80° of articulation in the ball joint. When trucks are lifted, caster and camber angles are affected that can lead to poor handling characteristics such as ‘wandering’. SPC control arms have positive caster built-in for lifted vehicles to restore alignment angles and driv ability. The patented ball joint design allows the tire to be positioned correctly in the wheel well and additional adjustment in the OE lower arms can maximize placement for oversized tires to avoid fender trimming. If replacement lower adjustment cams are needed, see part #86250 or #86252. Sold as pairs. US Patent No. 7,513,514.