TIAGO TIGOR CNG - SERVICE MANUAL

STEERING_MANDO 21 9. WHEEL ALIGNMENT Wheel alignment is a procedure of aligning wheels according to the specifications. The purpose of these adjustments is to give maximum tire life and vehicle-travel that is straight and true when driving along a straight and level road. A correct wheel alignment is necessary because it affects directional stability, tire tread wear and vehicle’s safety. Warning signs of improper wheel alignment include steering wheel shimmy, a constant steering pull to one side, tire squeal noises when making turns, excessive vibration as speed accelerates, and changes in direction after a car has hit a bump on the road. If any of the above symptoms are noticed, wheel alignment becomes necessary. Wheel alignment should be done at the time of fitting new tires and thereafter at regular intervals. Wheels which may be only a fraction out of alignment can scrub or drag along the road instead of rolling along it. Normally overall wheel alignment refers to the procedures used to check and adjust the steering system, including the camber, caster, and toe. Basically toe is a measurement of how much the front and/or rear wheels are turned in or out from a straight ahead position. When the wheels are turned in, toe is positive (+). When the wheels are turned out, toe is negative (-). The purpose of toe is to ensure that the wheels roll parallel. Toe also serves to offset the small deflections of the wheel support system that occur when the vehicle is rolling forward. In other words, with the vehicle standing still and the wheels set with toe-in, the wheels tend to roll parallel on the road when the vehicle is moving. Toe settings affect three major areas of performance: (a) Tyre wears (b) Straight-line stability and (c) Vehicle handling characteristics Following precautions are to be taken before commencing wheel alignment: 1. Car should be unladen and parked on level surface. 2. Front and rear tires should be inflated to correct pressure (28 and 32 psi respectively) 3. Ensure that bushes in the front/rear suspension are in satisfactory condition. 4. Ensure that front rear & suspension fasteners are tightened to their specified torques. 5. Also ensure that there is no visible damage to any of the suspension parts like lower link bushes and struts. 6. Ensure that there is no play in steering linkages and suspension ball joints. 7. Ensure no tyre wear on any wheels. If so replace the respective tires. For steering geometry adjustment (wheel alignment) on vehicle – Refer Wheels & Tyres section in Suspension chapter Wheel lock angle (Outer) 31.96° Wheel lock angle (Inner) 36.59° NOTE: a) Please follow manufacturer’s (of tire replacement machine) manual for wheel alignment instructions, recommendations and any other additional information. b) All adjustments for wheel alignment are to be done in UNLADEN CONDITION ONLY. c) Only TOE-OUT value at front has to be adjusted while doing wheel alignment. Rest of the values remains fixed i.e. NO adjustments are required. Refer the given table for standard values.