Toyota Hilux: AN120 Front Upper Control Arm Bush Premature Wear

The AN120 HiLux double-wishbone front suspension uses rubber-bonded upper control arm bushes that have demonstrated premature deterioration well inside expected service life. The bushes are pressed into a steel housing on the upper arm and are subject to high radial and axial loads on corrugated roads and off-road surfaces typical of Australian and New Zealand use. The rubber compound in early production batches delaminates from the steel outer sleeve, allowing the arm to shift unpredictably under braking and cornering loads. This causes vague steering, clunking over bumps, and measurable changes in caster and camber geometry that accelerate front tyre wear. The failure is progressive and often goes unnoticed until the bush is near complete collapse. Toyota issued revised bush specifications in later production, but in-service vehicles may not have had the improved components fitted at the time of service.

• Clunking or knocking from front suspension over bumps or rough road surfaces
• Vague or imprecise steering feel, particularly under braking
• Uneven or accelerated front tyre wear, especially inner shoulder
• Vibration through steering wheel on corrugated roads
• Vehicle pulling to one side under hard braking

Visually inspect the upper arm bush housings for cracking, deformation, or separation of the rubber from the metal sleeve. Check for grease or black rubber dust around the bush area. Have a wheel alignment check performed and compare caster readings to specification — out-of-spec caster is a strong indicator of bush collapse. If a workshop inspection is possible: With vehicle on a hoist, grasp the front wheel at 12 and 6 o'clock positions and attempt to rock it in the vertical plane — any visible movement at the upper control arm pivot indicates bush wear.

Parts involved: Ball joint.

$650 to $1,450 at New Zealand independent workshop rates. That is for this job on its own, not for the car.

An estimate, in NZD, for the repair as normally carried out. What a specific car costs depends on which part has failed and what it damaged on the way — treat this as the floor for a negotiation, not a quote.

• “Have the front upper control arm bushes been inspected or replaced?”
• “Has the vehicle had a wheel alignment recently, and were any measurements out of specification?”
• “Is there any clunking or knocking from the front suspension over rough ground?”
• “What proportion of the vehicle's use has been off-road or on gravel roads?”

The failure described above is documented in published sources — owner forums, technical service bulletins, recall notices and workshop write-ups — held in our fault database. The inspection instructions and the cost estimate are KickTyres’ own interpretation of them, and it is a starting point for an inspection rather than a manufacturer statement.