My 2008 Highlander had an alignment problem and caused some (or maybe all) of the tires to feather. I got the alignment fixed but the tires are still quite noisy when I drive and they seem to be getting worse. I've had them rotated once right after the alignment in the early summer.
Is there any way of fixing this other than spending $700 on new tires when these have 1/2 to 2/3rds of their life left?
Is there any way to know if the people that did the alignment did a good job? It doesn't pull to either side when I drive but it didn't prior to the alignment either. I'm worried that they did a bad job and that's why the noise is getting worse and now parts of the vehicle resonate at higher speeds. I hesitate to take it to another alignment shop since they might charge me for doing nothing and just tell me the last alignment was bad.
Looking at another question on here I realize it could partially be a tire balance issue. That might explain the vibration on the freeway but not the droning noise.
Update: It turned out the tires were not the source of the noise like I had believed. I had a wheel bearing failing and when I fixed it the noise continued, not because of the tires but because I had a different wheel bearing failing at the same time. After fixing that one it runs quietly again. I'm going to leave this question here since the answers contain potentially useful information about tire truing. Mods: feel free to delete if you think it has no value.