ASE A4 Suspension and SteeringWheel Alignment Diagnosis, Adjustment, and RepairMedium
A vehicle is brought in for a four-wheel alignment. The technician performs the pre-alignment inspection and finds no visibly damaged components. During the alignment, the machine measures a rear total toe of -0.25 degrees. The specification is +0.05 degrees +/- 0.05 degrees. The vehicle has an independent rear suspension with eccentric bolts for toe adjustment. How should the technician adjust the rear toe?
- AAdjust both rear eccentric bolts to move the front of the wheels outward.
- BAdjust both rear eccentric bolts to move the front of the wheels inward.
- CAdjust both rear eccentric bolts to move the top of the wheels outward.
- DAdjust both rear eccentric bolts to move the top of the wheels inward.
Show answer & explanationAnswer & explanation
Correct answer: B. Adjust both rear eccentric bolts to move the front of the wheels inward.
A negative total toe reading (-0.25 degrees) indicates that the rear wheels are in a toe-out condition (front of wheels pointing away from each other). The specification is for a slight toe-in (+0.05 degrees). To correct toe-out and achieve toe-in, both rear eccentric bolts should be adjusted to move the front of the wheels inward, bringing them closer together.
Why the other options are wrong
- A. Moving the front of the wheels outward would increase toe-out, worsening the condition.
- C. Adjusting the top of the wheels outward affects camber, not toe.
- D. Adjusting the top of the wheels inward affects camber, not toe.
Rear Toe Adjustment
Rear toe is the inward or outward angle of the rear wheels. It is commonly adjusted using eccentric bolts on the lower control arms to move the front or rear of the wheel.
- Negative toe = toe-out (front of wheels apart).
- Positive toe = toe-in (front of wheels closer).
- Adjusting eccentric bolts moves the wheel pivot point.
Memory trick: Rear toe's read, front's in or out, eccentric's turn clears all doubt.