An alignment is much more than pointing the tires straight ahead. It is looking at angles and adjusting them to make the car or truck track the best on the road according to the manufacturer. Camber, caster, toe and the thrust angle all play a very important part in how your car drives and how straight it drives on roads with a crown. An Experienced technician will be able to tell you how your car or truck drives just by looking at the alignment. Its also crucial to annually check your alignment because it does not take much for it to fall out of alignment. Potholes and separation cracks in the road continuously beat away at the suspension and your alignment.
Camber is the angle when looking head on into a tire. Is it straight up and down or leaning inward or outward? Some camber is good and too much can be bad and cause excessive tire wear. Some European cars like a lot of camber for the road handling benefits. BMW for example has a lot of negative camber and contributes to their racecar like driving experience. When driving behind a BMW next time you will see the top of the tire leaning in towards the car. Your basic commuter car on the other hand will have closer to zero degrease of camber. This is good for fuel economy and overall even tire wear. Excessive camber can cause extreme inside tire wear and cupping if the tread is an off-road style truck tire.
Caster is only measured on the front of the car where the tires turn back and forth. Caster does not cause tire wear but does contribute significantly to how your car handles on a road crown and the highway. Think of a time that you were turning and then let the steering wheel slide through your hands as it returns back to center. That is caster at work. Because of caster your steering wheel likes to sit strait ahead and track strait down the road. Now to picture caster you need to draw a line from the top ball joint or pivot point through the bottom ball joint. That is the axis on which the tire turns from side to side. Positive caster is where the line tilts back towards the driver and this Is what we want. Negative caster would be like the wheels on a shopping cart and it would be uncontrollable on a car. A little bit less positive caster on the driver’s side versus the passenger side is desired for road crown and helps the car track strait on a road that is slanted to side instead of having to fight it.
Toe is the angle you think of most when driving a car or truck. Are the wheels pointed straight ahead? Is your steering wheel strait when driving? I hope so! This angle does cause tire wear and is usually adjusted when doing an alignment. This angle is adjusted front and rear and should be checked and adjusted annually and when you get new tires to make them last as long as humanly possible. Alignments are the best insurance to make sure you are getting the best bang for your buck on those new shiny rubbers and make sure it is a four-wheel alignment.
Thrust angle is rarely talked about but is important in understanding why a vehicle may be “dog tracking” (driving down the road at an angle). This angle is in the rear of the car or truck and indicates where both of the rear tires are pointed. The rear of the car is what actually determines the direction of the car. Are they straight ahead or off to one side or the other? In large trucks it’s a good way to spot damaged suspension components or that something is bent in a rear solid-axle truck or car. A seasoned technician will look at this angle before adjusting the front so they can get the steering wheel as strait as possible.
Now you know why you need an alignment! Remember potholes here in Colorado Springs are brutal and constantly taking a toll on your alignment and the suspension parts that make all of that movement possible. From ball joints, control arm bushings, tie rods and your shocks all taking the brunt of our rough roads its good to have a seasoned mechanic “shake-down” the suspension before an alignment to see If anything needs replacement before an alignment. At Honest Accurate Auto Service, we do just that and we show you if anything is wrong.