Can turning the upper strut mounts affect toe?

slavrenz

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2001 Mazda Protege LX 2.0
Took my car for an alignment this afternoon after installing new struts...$170! Toe was too negative in all four corners, which was fine, but camber and caster were spot on. Still, they charged me an extra $75 to remove the front right strut and rotate the upper strut mount for unknown reasons.

I'm going back in on Monday to talk to the owner and get some answers...however, I don't want to look like an idiot insisting that certain things don't impact other things. Can anyone confirm for me that rotating the upper strut mounts will not have an effect on toe settings? I'm sure they'll say that the strut mount was rotated to compensate for excessive toe-in, and I just want to be able to say, "Actually, no, the only thing that will affect toe-in is the tie rods".

From my workshop manual, it appears that caster/camber = rotate strut mounts; toe = rotate tie rods. It appears that the two systems are independent, right?
 
From my workshop manual, it appears that caster/camber = rotate strut mounts; toe = rotate tie rods. It appears that the two systems are independent, right?
Rotating your strut mounts may affect your toe in but you don't adjust your toe in by rotating the strut mounts.

You rotate your tires rods to adjust your toe in as you stated.

The the only reason they should remove the strut is to adjust for caster or camber.
 
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So, if the "Before" and "After" camber/caster readings were identical for both front tires, you think I'm justified in questioning why I was charged an extra $75 to remove one of the struts in order to rotate the upper strut plate?

What confuses me even more is that even if they did rotate the strut mount like they said, the camber or caster should have changed. On the right tire there was no difference, and the left tire changed by 0.1 degrees (which, according to my repair manual, rotating the mount changes these readings by a minimum of 0.5 degrees).
 
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Yes,... rotating the strut plate should yield difference caster camber numbers.
They probably put it back in the same position they took it out from.
 
So, I talked to the garage this morning, and they basically said, "Yeah, so the way our software works is that the 'before' reading was from after the technician rotated the strut plate but before he made the toe adjustments, so that's why nothing appeared to be off". So, what am I supposed to say in that case? I basically have no way of knowing whether or not they are feeding me complete BS, but I don't want to go making blindingly wild accusations about dishonesty.

I've never worked with an alignment rack before, so I don't know how the software functions - does this sound legit to anyone?
 
On most of the alignment software you need to reposition the vehicle completely after every time you remove a wheel what you would need to do to remove a strut. And when that occurs the computer resets the base measurement to where you restart the alignment. The alignment technician should have printed out and initial measurement from before any work was started in this case. I'm not an expert I just do it for a living. Good luck man
 
On most of the alignment software you need to reposition the vehicle completely after every time you remove a wheel what you would need to do to remove a strut. And when that occurs the computer resets the base measurement to where you restart the alignment. The alignment technician should have printed out and initial measurement from before any work was started in this case. I'm not an expert I just do it for a living. Good luck man

Yes and no. Depends on the alignment rack and if the tech knows what he's doing. Using the hunter rack I did at school and the first shop and then the different hunter rack at the dealership I worked at, it's certainly possible to keep the original before reading but you have to not completely restart the alignment. An inexperienced tech (or just nobody told him that trick) could certainly clear the original "before" reading. They might be totally honest with you or they might be blowing wind up your butt. no way to prove it. There are some places (mostly in california) that if a shop cannot back up a repair with documented measurements you can get out of paying but most places aren't like that. Another route you can take is if the additional bill deviates by more than x% from the original quote, they have to contact you and ask if you want the repair done before doing it and charging for it (the x varies by state and by shop. where I used to work in IL the sign behind the counter said 10%). so if you go in for a $75 alignment and no mention is made of other charges (other than tax and like fees) they have to call you if it's going to me more than $7.50 more than the original quote. You'd still owe for the alignment but not the unapproved work. However if they say it'll be $75 for the alignment and more to do the adjustments depending on the car and you say OK go ahead, it's a legal grey area and they could probably get away with it.

Your best time to argue was at the time of service when you picked up the car and got the bill. After paying, you can argue but they already have your money. If you want it back, you could hire a lawer but that's a lot more than $75 and results will vary by state and locale.


Alignments are always set caster then camber then toe. This is done because each affects the next. There are exceptions around camber/caster setting but toe is always affected by camber. While it's certainly possible to design a suspension system that it doesn't, it's less practical and compact than everything in production.
 
If you remove a strut and rotate the mount you would have to remove the wheel. If you rove the wheel how would you be able to retain an accurate measurement on the mirror you had to remove.Also never done caster first. It's not even greatly adjustable on most vehicles. I have alway adjusted camber first, taking into account camber if applicable. Then finally toe it in. Maybe I'm wrong in my methods. But it works for me and seems to be the fastest way on a john beam alignment machine.
 
If you remove a strut and rotate the mount you would have to remove the wheel. If you rove the wheel how would you be able to retain an accurate measurement on the mirror you had to remove.Also never done caster first. It's not even greatly adjustable on most vehicles. I have alway adjusted camber first, taking into account camber if applicable. Then finally toe it in. Maybe I'm wrong in my methods. But it works for me and seems to be the fastest way on a john beam alignment machine.

It's possible to rotate the mount while the strut is assembled. probably even with it bolted to the hub. PITA but possible.

I could have camber/caster order flipped, it's been 2 yrs since I got out of working on other people's crap daily. you're right that caster is either not adjustable or minimally adjustable on most vehicles. Or, like the P5, only adjusted at the same time as camber by rotating the strut mount or similar.

I meant if you know what you're doing on the hunter machines I used, it's possible to retain the original before-adjustment numbers through a wheel compensation to compare to the after-adjustment numbers on the printout. No idea about different brands and heck, don't even remember exactly how on a hunter since it's been a while.
 
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