If your car does not steer straight, then you may have a wheel alignment problem. You may have your alignment checked and discover that it is within the acceptable range of specs for the application but still it does not steer straight. This is because some vehicles are more sensitive to slight variations in alignment that others and the same goes for motorists
Most experts agree that wheels should be aligned to the preferred alignment settings rather than accepting anything that is between the minimum and maximum values because preferred settings are closer to the mark than the minimum or maximum values
For a four wheeled vehicle to travel in a straight line, these conditions must be met
i. The four wheel must point in the same direction
ii. The amount of rolling resistance offered by all four wheels must be the same and this must include caster effect between the two front wheels
iii. There must be no play in the steering or suspension linkage that positions the wheels
If these conditions are not met, steering properly becomes a challenge as the tendency for vehicle to drift to one side increases
TOE ALIGNMENT-- Toe represents the angle derived from pointing the tires inward or outward from a top-down view – much like looking down at your toes and angling them inward or outward. Properly aligned toe is vital to even tread wear and extended tire life. If the tires are pointed inward or outward, they will scrub against the surface of the road and cause wear along the edges. Sometimes however, tread life can be sacrificed for performance or stability
Positive toe is when the front of both tires begins to face each other. Positive toe allows both wheels to constantly generate force against each other, which reduces turning ability. However, positive tow creates straighter driving characteristics
Negative toe can be found in front wheel drive vehicles for the opposite reason. Their suspension arms pull slightly inward, so a slight negative toe makes up for the drag and level out the wheels at speed. Negative toe increases a cars cornering ability. When the vehicle turns inward towards a corner, the inner wheel is angled more aggressively and because its turning radius is smaller than the outer wheel due to the angle, it pulls the car in that direction. Negative toe decreases straight line stability as a result. Any slight change in direction will cause the car to hint towards one direction or the other
CAMBER ALIGNMENT-- If your vehicle's camber is set to factory specs, the wheels should be more or less perpendicular to the road at normal ride height. Camber differs as suspension travels through jounce and rebound, but this should not be a problem as long as the camber changes are the same side-to-side. Manufacturers allow for a lot of camber variations
WHAT DO YOU DO IF YOUR VEHICLE HAS NO FACTORY CAMBER ADJUSTMENTS?
ANS--- Check the suspension and make sure nothing is bent, worn out or broken as these can throw camber off the mark. The easy way to do this is by checking and comparing SAI(Steering Axis Inclination) readings side to side, the right and left SAI readings should be within half a degree of each other. If SAI readings are ideal, then some alignments aid may need installment
CASTER ALIGNMENT-- Caster readings should be set to the preferred specs and be within half a degree side-to-side just like camber
If there is too much difference side-to-side readings, this can make the vehicle hint towards the side with the least caster. Higher caster increases steering stability because it forces the suspension to lift when the wheels are steered, while lower caster decreases steering stability. Sometimes steering wander can be a problem if the front wheels have insufficient caster. Steering pull that is caused by road crown can sometimes be compensated by adding positive caster to the left front wheel. For out of range caster, check out for worn strut or control arm bushings, mislocated MacPherson strut tower or a bent lower control arm
Most experts agree that wheels should be aligned to the preferred alignment settings rather than accepting anything that is between the minimum and maximum values because preferred settings are closer to the mark than the minimum or maximum values
For a four wheeled vehicle to travel in a straight line, these conditions must be met
i. The four wheel must point in the same direction
ii. The amount of rolling resistance offered by all four wheels must be the same and this must include caster effect between the two front wheels
iii. There must be no play in the steering or suspension linkage that positions the wheels
If these conditions are not met, steering properly becomes a challenge as the tendency for vehicle to drift to one side increases
TOE ALIGNMENT-- Toe represents the angle derived from pointing the tires inward or outward from a top-down view – much like looking down at your toes and angling them inward or outward. Properly aligned toe is vital to even tread wear and extended tire life. If the tires are pointed inward or outward, they will scrub against the surface of the road and cause wear along the edges. Sometimes however, tread life can be sacrificed for performance or stability
Positive toe is when the front of both tires begins to face each other. Positive toe allows both wheels to constantly generate force against each other, which reduces turning ability. However, positive tow creates straighter driving characteristics
Negative toe can be found in front wheel drive vehicles for the opposite reason. Their suspension arms pull slightly inward, so a slight negative toe makes up for the drag and level out the wheels at speed. Negative toe increases a cars cornering ability. When the vehicle turns inward towards a corner, the inner wheel is angled more aggressively and because its turning radius is smaller than the outer wheel due to the angle, it pulls the car in that direction. Negative toe decreases straight line stability as a result. Any slight change in direction will cause the car to hint towards one direction or the other
CAMBER ALIGNMENT-- If your vehicle's camber is set to factory specs, the wheels should be more or less perpendicular to the road at normal ride height. Camber differs as suspension travels through jounce and rebound, but this should not be a problem as long as the camber changes are the same side-to-side. Manufacturers allow for a lot of camber variations
WHAT DO YOU DO IF YOUR VEHICLE HAS NO FACTORY CAMBER ADJUSTMENTS?
ANS--- Check the suspension and make sure nothing is bent, worn out or broken as these can throw camber off the mark. The easy way to do this is by checking and comparing SAI(Steering Axis Inclination) readings side to side, the right and left SAI readings should be within half a degree of each other. If SAI readings are ideal, then some alignments aid may need installment
CASTER ALIGNMENT-- Caster readings should be set to the preferred specs and be within half a degree side-to-side just like camber
If there is too much difference side-to-side readings, this can make the vehicle hint towards the side with the least caster. Higher caster increases steering stability because it forces the suspension to lift when the wheels are steered, while lower caster decreases steering stability. Sometimes steering wander can be a problem if the front wheels have insufficient caster. Steering pull that is caused by road crown can sometimes be compensated by adding positive caster to the left front wheel. For out of range caster, check out for worn strut or control arm bushings, mislocated MacPherson strut tower or a bent lower control arm
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