SPC Performance Alignment Caster / Pinion Angle Bolt Kit
SPC Performance Caster & Pinion Angle Bolt Kits: Precision Alignment for Lifted Trucks and Off-Road Builds
When you raise a truck or SUV with a suspension lift, the factory axle mounting geometry is thrown off — caster angles shift, the driveshaft pinion points the wrong direction, and tire wear and handling suffer as a result. SPC Performance engineered their Alignment Caster / Pinion Angle Bolt Kits specifically to address this problem, offering one of the most trusted drop-in solutions in the industry for restoring proper front-end geometry without major fabrication work.
Who Makes These Kits — and Why It Matters
Founded in 1971, SPC (Specialty Products Company) has grown into the world leader in the development, manufacturing, and sales of wheel alignment parts. The SPC Performance brand specifically targets the off-road, track, and enthusiast markets, while the Specialty Products label serves traditional aftermarket and OE service channels. That deep institutional knowledge of alignment geometry — built over five decades — is baked directly into every cam bolt and eccentric they produce.
SPC is proud to be an ISO 9001 & IATF 16949 certified company, meaning their manufacturing processes meet the same rigorous quality standards demanded by original equipment suppliers. SPC still makes many of its parts in its own facility with extensive mill & lathe capabilities, including laser cutting, forming, and welding.
How SPC's Caster / Pinion Angle Bolt Kits Work
These cam bolts replace the front axle bolts to provide caster and pinion angle adjustment of up to 3 degrees total change. Rather than requiring a full control arm swap or bracket modification, the kits use eccentric cam-style replacement bolts that rotate within the existing axle bracket holes to dial in the correction you need. Depending on the specific kit, adjustment ranges vary:
- The SPC 82390 (for Jeep Wrangler JK, 2007–2018) provides a caster and pinion angle range of ±1.50°.
- The SPC 82385 replacement cam bolts offer caster and pinion adjustment up to ±2.00 degrees, allowing you to achieve desired alignment settings with or without suspension lift kits while adding positive caster for improved tracking.
- The SPC 82395 is designed to replace non-adjustable or corroded OE bolts on Dodge 3/4 and 1-ton trucks, restoring ±1.5° of caster and pinion angle change.
- The SPC 82375 kit is designed specifically for the Jeep Wrangler JL and provides ±1.5 degrees of adjustment.
Important Installation Note
To gain the full range of adjustment these cam bolts provide, the OEM bolt holes in the axle brackets may need to be elongated — SPC offers a dedicated knock-out punch (part #74910) to make that modification cleanly and precisely. Keep in mind that front caster will also change as you adjust pinion angle, so it's best to make corrections with an alignment rack to confirm final settings.
Race-Proven Engineering for Street and Trail
SPC started in the business of providing alignment shops with the parts and tools to get the job done, and it was a natural progression that these components found their way into performance and racing applications — particularly because lowered and lifted vehicles affect alignment angles and often need adjustments beyond factory component capabilities. SPC components are race proven, having endured the harsh environments that only competition can provide — and if a part can survive that, it's more than up to the task for daily driven or trail-going vehicles.
Whether you're correcting caster wander on a lifted Wrangler or addressing driveline vibration caused by pinion angle on a lifted half-ton, SPC Performance's bolt kits offer a cost-effective, precision-engineered fix backed by decades of alignment expertise. Browse the full range of Alignment Caster / Pinion Angle Bolt Kits or explore everything SPC Performance has to offer across their complete suspension and alignment lineup.