TOYOTA 48190-0K030 Eccentric Control Arm Bolt

The genuine TOYOTA 48190-0K030 eccentric control arm bolt (suspension camber adjusting bolt) is a critical fastening and adjustment component in the vehicle's suspension system. This specially engineered part enables precise, sub-millimeter adjustment of wheel camber (and, where applicable, caster) during the wheel alignment process.

Technical Features and Function

Rotating the eccentric bolt head and its corresponding eccentric washer shifts the mounting position of the control arm within the suspension frame, directly modifying the suspension geometry. This adjustment is essential for maintaining straight-line tracking, even tire wear, and cornering stability.

• Material Quality: High-tensile, hardened alloy steel engineered to withstand continuous dynamic and static suspension loads.
• Surface Treatment: Specialized anti-corrosion coating (galvanized or phosphated finish) providing reliable protection against moisture, road grime, and winter de-icing salts.
• Design: Precision bolt shank with an integrated eccentric cam plate for accurate positioning and non-slip clamping.

When is Replacement Necessary?

Suspension adjustment bolts are mounted in exposed locations on the vehicle undercarriage, making replacement necessary under the following circumstances:

• Seizing (Corrosion): The bolt frequently rusts tight inside the metal sleeve of the control arm bushing. In this state, suspension adjustment becomes impossible, and the bolt often requires destructive removal (cutting).
• Thread Damage: Threads damaged by over-tightening or improper prior servicing can no longer maintain specified torque, leading to shifting alignment settings.
• Mechanical Deformation: Severe mechanical shock (such as striking deep potholes or curbs) can bend the bolt, causing persistent wheel geometry inaccuracies.