Steering Pull and Tyre Wear
A 2018 Ford Ranger (60,000 km) pulls to the right and the front tyres show uneven wear: the outer edge of the left front tyre is worn significantly more than the inner edge. The owner recently had new tyres fitted and a wheel alignment at a chain store. You check tyre pressures: all at 35 psi (spec 35 psi). You inspect the suspension: no obvious play in ball joints or tie rods. A alignment check shows: front left camber -0.5° (spec -0.5° ±0.5°), front right camber -1.2° (spec -0.5° ±0.5°), toe left 0.1°, toe right 0.1° (spec 0.1° ±0.1°). The steering wheel is off-center when driving straight.
1. What is the most likely cause of the pull and uneven tyre wear, and what further checks would you perform?
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The pull to the right and uneven wear on the left front outer edge suggest a camber issue on the right front. The right front camber is -1.2°, which is outside spec (-0.5° ±0.5°), meaning too much negative camber. This can cause the tyre to lean inward at the top, wearing the inner edge, but the left front outer edge wear is odd. Actually, if the vehicle pulls right, the right front tyre may be dragging, causing wear on the left front outer edge due to scrubbing. Also, the steering wheel off-center indicates the toe may be incorrect or the steering angle sensor needs reset. Further checks: 1) Inspect for bent strut or control arm on right front; 2) Check subframe alignment; 3) Verify alignment machine calibration; 4) Check steering rack for play; 5) Perform a road test with steering wheel centered to assess pull.
2. The customer wants the alignment redone under warranty. What would you do and what would you document?
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First, verify the alignment readings with a second machine or by rechecking on a level surface. If the right front camber is indeed out of spec, inspect for damaged components (strut, knuckle, control arm). If no damage, adjust camber if possible (some vehicles require shims or offset bolts). Document before and after readings, including the out-of-spec camber. Note the steering wheel off-center and correct by adjusting toe while holding the wheel straight. Provide the customer with a printout. If the previous alignment was done incorrectly, inform the customer and offer to redo it. If damage is found, explain that warranty may not cover it. Keep records for potential liability.