NISSAN 40571-01J00 Kingpin Bearing Shim

This genuine NISSAN (SKU: 40571-01J00) kingpin / swivel bearing shim is a precision component essential for the accurate alignment and adjustment of the vehicle's front suspension and steering system. On solid axle front suspensions, proper kingpin bearing preload directly influences vehicle handling and directional stability.

Function and Importance

The primary function of the shim is the micrometer-precise adjustment of the axial play of the kingpin bearings. Bearings set too loose cause unstable steering, wheel wobble (shimmy), and accelerated wear of suspension components. Conversely, an overly tight setting increases friction, makes steering stiff, and causes bearing overheating followed by premature failure. Genuine Nissan shims guarantee a perfect fit and preload conforming to factory specifications.

Technical Specifications

• Manufacturer: NISSAN OEM
• OEM Part Number: 40571-01J00
• Part Type: Kingpin Bearing Shim
• Material: Premium-grade hardened spring steel resistant to continuous mechanical stress and corrosion
• Fitting Position: Front axle, under the kingpin mounting bracket

Symptoms of Incorrect Shimming or Wear

• Vague, imprecise steering feel or excessive free play in the steering wheel.
• Severe front suspension vibration occurring at high speeds or over road imperfections.
• Abnormal, uneven tire wear.
• Premature mechanical damage or scoring of the kingpin bearings.

During suspension overhaul and kingpin bearing replacement, it is always recommended to inspect the preload and replace the shims as necessary to restore factory specifications.