You may, at some point, have heard someone refer to a “tire alignment” as opposed to a “wheel alignment.” What’s the difference?
The quick answer is, “nothing.” The two terms are synonymous with each other, like “wheel balancing” or “tire balancing.”
For these purposes, though, we’re going to use the phrase “wheel alignment.” Every car is engineered with wheels that are set at very specific angles, as related to the chassis, each other, and an imaginary straight line. These angles are designed and optimized for the best ride quality, handling and steering response possible, and that’s how your car leaves the factory. Those settings will drift out of spec, though, as the steering and suspension absorb normal wear and tear.
Signs of a Poorly Aligned Vehicle
The most noticeable and most common symptom of improper wheel alignment is a persistent pull to one side on straight pavement. That pull is due to a tire that is trying to force the vehicle to one side due to an improper alignment angle. This condition is called “toe-in” or “toe-out,” referring to the direction that wheel is pointed in, relative to a straight-ahead orientation.
That out-of-spec tire will be dragged along by the other tires and will show uneven tread wear as the tread is “scrubbed” along an inside or outside edge. That extra friction and drag also hurts fuel economy (and invalidates tire warranties).
These are a checklist of alignment issues:
Constant pull to one side, even with proper tire inflation, no crosswinds and flat, non-crowned pavement
Four Wheel Alignments
Many newer vehicles are designed with adjustable rear suspensions, to facilitate four-wheel alignments. Four-wheel alignments set the front tires’ angles at a proper spec in relation to the back wheels – this angle is referred to as ‘thrust angle.” It’s a more sophisticated and expensive alignment procedure, but it pays off in handling and drivability qualities.
Alignments are performed on a piece of equipment called an alignment rack, with the technician measuring and analyzing all the angles of a vehicle’s wheel alignment and making minute adjustments to bring it back to spec again. Often on older vehicles with many miles on them, suspension and steering parts are worn and have enough play and slop that they may have to be replaced before a proper alignment can be done
To give you an idea of how a tiny adjustment can make a difference, consider this. If a car with a steering angle that’s off by only 1/8” was left on its own on a straight road, with no steering input from the driver, it would drift 28 feet off of a straight line over the course of a mile!
It’s annoying and tiring to drive a vehicle that’s out of alignment…and why spend money replacing tires before their time? Have you recently sustained a hard hit on a curb, a pothole or railroad tracks? Are you noticing worn tires or a persistent pull to one side while driving? Give us a call at Don Duncan’s All American Auto and Tire Centers in Montgomery, AL and let us put your vehicle on the alignment rack!