Product Specification

Product Function Description

The steering knuckle bushing (part number 90381-30006) is a critical component of your Toyota vehicle‘s front axle and steering system. Its primary function is to serve as the bearing surface between the steering knuckle and the kingpin (steering pivot pin), allowing the knuckle to pivot smoothly for steering while maintaining precise alignment. This solid bushing is pressed into the steering knuckle yoke bore and provides a durable, low-friction interface that supports the vertical loads of the front axle while enabling steering rotation. For Toyota Hilux, 4Runner, T100, and Land Cruiser models equipped with 4WD solid front axles, a properly functioning knuckle bushing is essential for precise steering control, stable handling, and safe vehicle operation.

Common Symptoms of a Failing Steering Knuckle Bushing

If you are experiencing any of the following symptoms, your steering knuckle bushing may be failing and in need of replacement:

• Excessive steering play or looseness: The steering wheel has excessive free play before the wheels respond – this indicates worn bushing allowing movement between the knuckle and kingpin

• Clunking or popping noises when turning: A metallic clunk or pop sound when steering or going over bumps – this suggests worn bushing creating metal-to-metal contact

• Steering wander or poor returnability: The vehicle wanders on straight roads or the steering does not return to center properly – this indicates bushing wear affecting knuckle alignment

• Uneven or irregular front tire wear: Front tires show uneven wear patterns – this can result from bushing wear causing alignment changes

• Vibration through the steering wheel: Steering wheel vibration that changes with road conditions – this indicates looseness in the knuckle pivot assembly

• Visible wear or corrosion on the bushing: During inspection, the bushing shows scoring, pitting, or deformation

If you have confirmed these symptoms through inspection, replacing the steering knuckle bushing is the recommended solution.

Product Attributes

Vehicle Fitment (Applicable Models):

4WD (four-wheel drive) heavy-duty off-road vehicles, pickups, and commercial vehicles manufactured between 1986 and 2004.

• Toyota Hilux (4WD Pickup): Classic 4WD versions such as LN107, LN111, YN63, etc.

• Toyota 4Runner (4WD SUV): 1986–1995 models.

• Toyota T100 (Toyota's early full-size pickup)

• Toyota HiAce (4WD Commercial Van): 4WD van series such as LH107, LH119, LH178, LH188K (including 5L diesel versions), etc.

• Toyota Granvia / RegiusAce

Component Location & Core Function

Location: The steering knuckle bushing is located inside the steering knuckle yoke bore at the top and bottom pivot points. It sits between the steering knuckle (outer) and the kingpin (inner), providing the bearing surface for the steering pivot. On 4WD Toyota solid axle applications, there is typically one bushing at the top of the knuckle and one at the bottom, though this specific part number is listed as the inner position.

Connections: The bushing is pressed into the steering knuckle yoke bore. The kingpin passes through the bushing, allowing the knuckle to pivot around the kingpin axis for steering. The bushing is retained by the knuckle housing and sealed by grease seals. Grease is applied between the bushing and kingpin to reduce friction and wear. The knuckle arm connects to the steering linkage to transmit steering input.

Core Function: The steering knuckle bushing serves as the bearing surface that allows the steering knuckle to pivot around the kingpin while supporting the vertical loads of the front axle. It maintains precise alignment between the knuckle and kingpin, ensuring accurate steering geometry. The bushing absorbs vibration and reduces friction, contributing to smooth steering operation. When worn, the bushing allows excessive movement that causes steering play, noise, and alignment changes.

Companion Parts for Installation

During major overhaul or chassis maintenance, this part is typically installed or used together with the following core components:

① Directly Connected External Part: Steering Knuckle
This bushing is pressed directly into the bore of the steering knuckle.

• Left Steering Knuckle OEM No.: 43212-35070 / 43212-35080 (varies slightly by model year)

• Right Steering Knuckle OEM No.: 43211-35070 / 43211-35080

② Core Drivetrain Component Passing Through: Front Drive Shaft / Inner CV Spindle
The shaft journal of the drive shaft passes directly through this bronze bushing and contacts it. It is usually serviced together with the CV boot.

• Front Drive Shaft Assembly OEM No.: 43430-35010 / 43430-35022 (depending on specific model year)

③ Seals That Must Be Replaced at the Same Time: Front Axle Oil Seal (Oil Seal for Steering Knuckle / Axle)
To prevent front axle gear oil or grease from leaking through the gap between the drive shaft and this bushing, a dedicated front axle oil seal must be installed on the outer side of the bushing. During repair, removing this bushing will damage the oil seal, so it must be purchased and replaced at the same time.

• Front Axle Oil Seal OEM No.: 90311-35018 / 90316-60002 (corresponding to specific HiAce or Hilux axle housing designs)

④ Optional Adjustment Shims and Outer Bushing

• Outer Bushing (Bush, Outer): Some models use a double-layer bushing design at this position. The outer bushing is typically coded 90381-30003.

• Drive Shaft Dust Spacer (Spacer): 90560-30005

Maintenance & Purchasing Tips

Pair Replacement: If your vehicle (such as an older 4WD HiAce or Hilux) produces a "clunk, clunk" metallic knocking noise from the front wheels on bumpy roads, or if the front drive shaft root repeatedly leaks oil, it is usually caused by excessive wear and play in this 90381-30006 bronze bushing. It is recommended to replace both left and right sides at the same time.

Professional Press-Fitting: This part is a copper / special metal solid bushing and must be pressed evenly into the steering knuckle bore using a hydraulic press and dedicated tooling. Never strike it directly with a hammer, as any deformation may prevent the new drive shaft from being inserted, or may cause high-temperature burning and damage.

Quality Assurance & Service Commitment

Quality Assurance:
Every component is manufactured under controlled production processes to ensure consistent dimensional accuracy and material integrity. Each unit undergoes the following quality checks before packaging:

• Dimensional inspection – critical dimensions (ID, OD, height) are verified against design specifications

• Material verification – bronze alloy composition and hardness are tested

• Surface finish inspection – bore and OD surface quality are visually verified

• Packaging inspection – each unit is sealed in protective packaging

Packaging Protection:
Each steering knuckle bushing is individually sealed in protective packaging to prevent contamination and physical damage during storage and transit. The packaging includes a clear part number label for easy identification.

Service Commitment:

 Related Product Recommendations

When replacing the steering knuckle bushing, it is often recommended to inspect and consider replacing the following related components at the same time.