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2011 GS Alignment Question

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Old May 22, 2014 | 11:16 PM
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Default 2011 GS Alignment Question

I bought the car in April, and the selling dealer installed new Michelin Super Sports on it.

I drove it from Dallas, TX to Northwest Illinois, so I put some 1100 miles on it. I've put another four or five hundred miles on it since I bought it.

After reading all the horror stories of worn out tires, I decided that getting an alignment sooner was better than later. There didn't seem to be any issues with the car with respect to handling, response, wandering, or anything else.

My local dealer has done pretty good work for me in the past, and I had a 20% off coupon that I needed to use, so I thought I'd give them a try.

I'd seen the recommendations for the Pfadt alignment, and took a copy of that with me when I spoke with the Service department. I told them that I didn't have any issues with the car, and I primarily wanted the alignment as a precaution, and that I was looking to balance tire life and good street handling (I have no plans to track the car).

When I picked the car up, the tech mentioned that he had some trouble setting the caster that I desired, but in my desire to get to the car, I failed to think through what he was saying, and I also failed to get a copy of the before and after settings.

Unfortunately, on my way home, I noticed that the car was now showing a strong tendency to drift right. I checked at various speeds and various roads, and they all resulted in the same behavior: release the wheel, and the car immediately starts drifting right.

I didn't drive the car over the weekend, and returned it to them Monday morning, describing what I'd observed. A few hours later, I got a call from them saying that the car was ready, the rightward drift was solved, and that the tech had set the car up to minimize tire wear.

So this time I remembered to get the before and after printouts, and it's clear that the tech didn't understand the Pfadt alignment specifications. Sadly, the car STILL has a tendency toward drifting to the right. Rather than taking the car back for a third time, I'm now trying to locate a good alignment shop in this area:

Dubuque, IA
Madison, WI
Rockford, IL
Sterling, IL

If you have a recommendation, please let me know.

Here is the data from the BEFORE and AFTER printout, along with the factory specifications that the dealer used:

Note: The BEFORE settings are what the Technician set it to originally. I don't know what they were when I bought the car (yes, I feel stupid).

FRONT CAMBER:
Factory Range: -1.6° to -0.4°
Pfadt Recommendation: -0.9° to -0.7°
Before: -1.0°(L), -0.7°(R)
After: -1.1°(L), -0.9°(R)
Cross Camber: -0.3°(Before), -0.1°(After)
Factory Specified Cross Camber Range: -0.6° to 0.6°

FRONT CASTER
Factory Range: 7.0° to 8.2°
Pfadt Recommendation: 7.5° to 8.5°
Before: 7.6° (L), 5.9°(R)
After: 7.4°(L), 8.1°(R)
Cross Caster: 1.7°(Before), -0.7°(After)
Specified Cross Caster Range: -0.6° to 0.6°

FRONT TOE:
Factory Range: -0.05° to 0.15°
Pfadt Recommendation: -0.17° to 0.0° (TOTAL Toe)
Before: -0.15°(L), -0.15°(R)
After: 0.04°(L), 0.08°(R)
Total Toe: -0.29°(Before), 0.12°(After)
Specified Total Toe: -0.10° to 0.30°

SAI (Left): 17.7°(Before), 17.4°(After)
SAI (Right): 9.1°(Before), 9.5°(After)

REAR CAMBER:
Factory Range: -1.8° to -0.6°
Pfadt Recommendation: -0.4° to -0.6°
Before: -0.5°(L), -0.6°(R)
After: 0.0°(L and R)
Cross Camber: 0.1° (Before), 0.0°(After)

REAR TOE:
Factory Range: -0.10° to 0.10°
Pfadt Recommendation: -0.17° to 0.0° (TOTAL Toe)
Before: -0.13°(L), -0.21°(R)
After: -0.01°(L), 0.02°(R)
Total Toe: -0.34°(Before), 0.01°(After)
Total Toe Specification: -0.20° to 0.20°

Thrust Angle: 0.04°(Before), -0.02°(After)


So I think it's clear that the Tech missed the Pfadt Toe specification, and read it as each side rather than total.

But what's up with the SAI? I thought those numbers were supposed to be very close between left and right (within a degree or so), and that >1 degree means that something is bent or broken.

Furthermore, there are still several settings that fall OUTSIDE the factory specifications!

I'd also like to know how close some of these readings need to be - for example, if all other readings were OK, does a cross camber actual reading of -0.1° mean that you're close enough?

I would appreciate any detailed explanation of these measurements, and if anyone can provide a recommended shop for me, I would be very grateful.

Thanks,
Steven
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Old May 23, 2014 | 06:39 AM
  #2  
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From: Laguna Woods, CA
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You're correct. According to the printout, they didn't align it properly. Give them one more shot. If they can't do it to spec, get your cash back. Not going back means you're out the bucks. That, to me, doesn't make sense. Why give them a pass? I don't buy that they *can't* get it aligned correctly.
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Old May 23, 2014 | 12:38 PM
  #3  
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Any thoughts on the wide disparity between the left and right SAI values?

It was my understanding that they should be close, and these are quite a ways apart.

With regard to returning to the shop for yet a third time, I really am not interested in doing that.

Steven
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