Alignments: to spec vs experience

I brought my Tacoma to get an alignment done the day after I had my lift and tires added. He aligned it to Toyota specs. It now seems to veer to the right, occasionally to the left.

I went back and explained it to the guy at the garage and he said the alignment guy has 22 years experience at it and its highly unlikely he made a mistake. I said I don't doubt that...but given the mods I have done maybe Toyota's specs aren't appropriate. He didn't disagree but said all they could do was align to specs. My question is could someone who has 22 years of aligning experience say to himself (or herself!) that hey...factory specs won't work here...I may need to bump up the caster, or make some further adjustments.

The garage suggested swapping the front wheels to see if it's a tire problem. I had them do it and it still seems the same although I haven't gone far yet. He said if it veers to the left more so than the right...basically opposite of my problem, then its not an alignment issue.

 

Get the alignment printout and post it here.

 

I had made a post about my problem awhile back but here is the printout I posted in that thread
http://www.tacomaworld.com/forum/2n...lling-right-since-tires-lift.html#post2264582

Just to add...given the alignment guy has 22 years experience, shouldn't he be able to tell me that factory specs won't be right given my mods? That is what bugs the hell out of me lol

 

i'm gonna say it's your caster giving you problems. it should be about a degree higher than it is now

edit: just read the other thread, looks like people already told you it was the caster

 

Oh, right. I remember that thread.

So, have you at least asked about that *way* out of spec SAI yet?

 

I brought it up but the guy behind the counter couldn't answer that and the guy who does alignments was out. I'll likely be going back over the next couple of days.

I guess what I am trying to figure out is do these guys know the difference when they align modded vehicles. Should this guy have known to increase the caster given the setup? how did someone figure that out in the first place?

 

Not really anything the alignment guy can do with the caster once you're lifted. The veering you get is likely due to the crown in the road. My truck is the same way. If everything else is in spec it won't affect the wear on your tires, but if it bothers you that much your only real "fix" is to get some new UCA's.

 

22 years of experience doing alignments on cars doesn't mean the guy knows what he's doing with lifted trucks.

 

regardles of the lift, the caster numbers in your post are low. they would even be low for a stock tacoma. they are however within spec. but within spec does not mean good.

the issue is that caster affects camber. you can have great caster and shitty camber or great camber and terrible caster. most people would rather have better camber and worse caster because bad camber will wear your tires funny and fast, whereas when your caster is off, it just messes a little with the driving characteristics

 

Here's the thing - he actually did a pretty bang up job of averaging everything out to get everything as close as possible to spec. So the answer to your stated question

Should this guy have known to increase the caster given the setup?

is yes. Yeah he did, and he gave you as much caster as he could given the limitation of your UCAs, even at the cost of increasing your camber a bit from optimal (around zero) but keeping it still in the range of allowed specification.

Contrast that with my alignment guy who optimized for tire wear by minimizing toe and camber, at the expense of giving me a near zero caster, making the truck a bit twitchier. (Which I'm OK with - informed decisions are the best ones.)

But even at near zero caster, my truck doesn't pull to one side or the other. It's a bit twitchy - that is - a tiny bump is more likely to send it to one side or the other, and it has less "return to center" after completing a turn, but it has no consistent pull to one side or the other.

If you're having a consistent pull, I'd look to your SAI or your tires.

Hijack: Worst pull I ever had was on a stock station wagon with some goodyear aqua tread tires. It was always noticable but particularly fatiguing on long trips. Drove all the way to LA with my knee pressed against the wheel so I wouldn't have to grip so hard with my hands. Turned out to be tires - once those tires wore out and we got some new ones, the pull went completely away.