Can I only get an alignment on new tires or is the salesman just being pushy?

Question

When purchasing new tires, the salesman is quick to recommend getting an alignment as well to prevent premature tire wear. I've even been told that you have to get the alignment done when the tires are new so they will allow the wheels to sit evenly and that worn tires will invalidate the alignment process since the wheels would then be "aligned" to the wear pattern.

In my head this seems to make sense because the wheels need to be aligned with the cars weight on the wheels to "set" the suspension, right? And if the wheels are resting on the ground (or the machine, whatever) wouldn't a very-unevenly-worn tire make the wheel crooked? Is this a real concern or is it a logical fallacy that the salesman is relying on?

Furthermore, is it really recommended that I get an alignment every time I get new tires? I've seen what a bad alignment can do to tires, so if the old ones are worn evenly, should I even bother?

Answer 1

You can get an alignment at any time. It's often a good idea to get one when you get new tires, just so you don't mess them up if you have any alignment issues. However, you should also get one done if you have any kind of suspension work done (new shock absorbers, new tie rods, etc.) While you probably don't need to have one done if your tire wear is even, it's probably a good idea, since I assume you only buy new tires every four or five years, and it's reasonable to have a new alignment done that often.

Answer 2

I've even been told that you have to get the alignment done when the tires are new so they will allow the wheels to sit evenly and that worn tires will invalidate the alignment process since the wheels would then be "aligned" to the wear pattern.

This is not true; the tire wear pattern has no affect on the measurements or adjustments.

If the wheels are resting on the ground (or the machine, whatever) wouldn't a very-unevenly-worn tire make the wheel crooked? is a real concern or is it a logical fallacy that the salesman is relying on?

Again not true. On an alignment machine the wheels sit on "turn tables". These allow the wheels to freely move anywhere in ground plane. This negates the forces that a worn or misshapen tire might try to exert on the suspension members that support it.

Furthermore, is it really recommended that I get an alignment every time I get new tires? I've seen what a bad alignment can do to tires, so if the old ones are worn evenly, should I even bother?

If the old tires are evenly worn then there is no dire need to check the alignment.

When to check wheel alignment.

1) An incident has occurred that could move the alignment angles. Such as one or more wheels hitting an object with sufficient force.

2) A crash that has damaged the body or suspension.

3) A part has been replaced that could change one or more suspension angles.

4) A period of time has past during which the rubber parts of the suspension have relaxed with age allowing the suspension to sag and move. This process takes years.

Notice that tires are not specifically mentioned in the above list. #4 is best taken care of on about the same time interval as tire replacement. So this is reason enough to get an alignment done with new tires.