Or how bad the roads you drive on are. If you are getting alignment done every year without any changes (no new wheels, tires etc..) and feeling a difference, then you are either A driving on some shitty roads or B driving the hell out of your car (and I don't mean just regular spirited driving).

bighead2 - when you've gotten your alignments this year, did you change anything? and how far off were they from desired settings?

 

I can't remember the specifics of my first alignment but my second was to UK specs so I changed everything (for the better I might add.)

I did my 3rd alignment for a few reasons, I wanted to go back to oem suggested settings to get some more rubber on the ground for winter time, at the same time I had some lane-drifting and my steering wheel was off center. The only thing that didn't require attention was my caster, everything else was off (my camber was fine but I reduced it to get more contact patch). Toe is the tire-killer, and consequently it was off by fair amounts on each corner.

 

I think there is more involved than just the roads and the way the car is driven. Some cars simply hold alignment better than others. I have always thought that the differences could be attributed to the care taken during the alignment; I've seen more than a few "alignment machine operators" who didn't even own a torque wrench.

I always get a before and after sheet showing the alignment specs of the car before and after realignment. Don't all modern alignment machines produce hard copy?

 

I rest my case in regards to Pep Boys

 

In the UK we have regular regional alignment meets by a guy who travels the country and only does this. He does it with your weight in the drivers seats. He looks at tire wear patterns and numerous other things I have never had from any garage doing it.
One other reason we use him. He has to calibrate his laser kit EVERYTIME he sets it up. Any of you guys seen a calibration certificate for the gear used on your cars?

Any way my point - not one of the cars going at any of the meets was with HUK's spec. Even 2 month old cars!

Personally I do it every time I change tires.