Car Aligned 3X still Drifts to Right

Having trouble getting my car aligned. Been back to the alignment shop 3 times. See alignment specs in pic.

The car is 06 GT with only 21K on it so I doubt any parts are worn. Big heavy E-force SC sitting on top has been on for years. Just changed to Brembos, 2010 GT 500 wheels, staggered 255/285 tires and Roush spring - mild ~3/4" drop front and rear. No alignment issues before this change. The alignment shop is a national chain but I only used them because they are close to home. So they are only going to put it "in-spec" not to a specific spec.

Based on these specs what would cause the car to drift right? Tested on a strip for road that 2 other cars go arrow straight for the full 2/10th mile. I've already tried rotating tires side to side.

I would say it's either a worn out bushing or the crown in the road

I was ruling out road crown as 2 other cars don't have a problem on the same stretch of road. Maybe this car is more sensitive to it.

Do you have an adjustable phb, rear lca's? If the car is lowered with the stock phb it will throw the track off slightly in the rear. Having the left rear hanging out left a slight amount. This could cause a slight right steer. Also, if your rear lca's are not adjusted correctly(if adjustable) and one is slightly longer than the other. Check the wheelbase on each side and make sure it matches. Something is slightly out of square on this suspension.


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Could also be a bad tire...I've had that happen.

I would lean towards a tire pull. Your alignment specs appear to be fine and not cause a pull/drift. Like said above, check your lca's for squareness if adjustable aswell as your panhard bar for center being you should have an adjustable one being dropped.


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IMO...I think your TOE numbers are not ideal and could result in the Pulling you are experiencing. I would take it to a shop willing to adjust it however you wish or how ever is needed to bring it more in line with "ideal".

I think TOTAL TOE should be set in such a way that it "ZERO's OUT" from one side to the other.

Many times front TOE is set on a street driven vehicle so that one side (lets say the Right side for example) is a negative # and the opposite side is set to a positive # of the same value. This is done to help avoid Pulling and or Tram lining when uneven road surfaces are encountered.

Just my 2cents..others may disagree

The rear suspension is still stock except for the Roush springs. No adjustable phb or control arms yet. I just measured rear offset...I'm 1/4" towards the drivers side.


The ride height which I think is only slightly lower than stock...
27 1/2 front
28 5/8 rear
I went with these springs as I thought I didn't need to go adjustable. I don't mind doing that if I need to.

It isn't toe, as your toe is leaning left.

Your camber is on the edge with the right side probably pulling you right. Get plates.


Also crown will affect you, especially with wider tires. May ask them to turn the wheel slightly right before aligning, so when you steer straight ahead, it will pull slightly left. This is assuming caster and camber are correct.

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In my experience, the repeatability of laser alignment racks is a little under 0.1deg, so your measurements look perfectly fine to me. I've also driven with 0.2deg difference in camber at your level and at ~-3deg, and I haven't felt the car pull to one side. If anything, your rear camber would cause the car to pull right from a small amount of camber thrust. Of course, your rear alignment isn't (easily) adjustable.

I don't know how much the axle is shifted in your car after lowering it 3/4", but I'm guessing that's the cause. As you lower the rear of the car, the chassis will shift right relative to the axle. When I first lowered my car (~1-1/4"), I also noticed a pull to the right before adjusting my panhard bar length. It might be a coincidence, but I'd suggest trying that first.

I'm also thinking axle shift with the lowered height. I had about 1" drop kit on my 2012, and it had some axle steer. I never got it worked out since I was ok with it (it was very little to me), and not a lot of shops around here would touch the rear suspension :/.

The front camber should be fine as they are both pointed inward. That wouldn't cause it to steer one direction over another. Especially with the 0.2* difference.

Another vote for the panhard bar. Front specs look ok. I'm kind of wondering how you have more toe in the rear than the front lol. Most of the rear specs should be pretty much 0 because of the solid axle. Could be funky readings due to the axle being shifted to the side if you didn't do a panhard bar.

Lack of an adjustable panhard would not cause such severe effects the OP is describing.

What tires are you running? Certain tires will cause tramlining much worse than others.

Running Conti DW

255/45/18 front
285/40/18 rear

The rear axle is shifted 1/4 inch to the drivers side. So an adjustable phb to pull it back 1/8 inch to center?

noldevin said:

Another vote for the panhard bar. Front specs look ok. I'm kind of wondering how you have more toe in the rear than the front lol. Most of the rear specs should be pretty much 0 because of the solid axle. Could be funky readings due to the axle being shifted to the side if you didn't do a panhard bar.

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Very few rear end assemblies are so true that they are 0 toe and camber. Just about all have a little. The amount shown is pretty normal from my experience.


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I bet that if you measure the wheel base on this car that the left side is 1/4-1/2" longer than the right. That my theory any way. All the line up specs are so close that they shouldn't make it pull or drift.


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I don't think the rear axle has anything to do with it. I've had my PHB way off before and it didn't cause a pull.

The easiest way to diagnose the tire pull is to unmount, swap and remount the front tires.

Already swapped the front tires side to side - no change still drifts to the right. Did not dismount from the wheel as they aren't directional tires.

Also I just measured wheel base. It looks to be 107 spot on each side although I'm not sure my method was perfectly accurate, I believe I'm within 1/4".

gus said:

The rear axle is shifted 1/4 inch to the drivers side. So an adjustable phb to pull it back 1/8 inch to center?

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That's a pretty small amount, so I'd agree that it's probably not the cause. Mine was off by closer to 3/4" when I had a slight pull.

To clarify - when you say it pulls to the right, do you mean that you actively have to steer left to keep the car in a straight line, or is the steering wheel just not straight while driving in a straight line? If the later, does the car still tend to go straight when you take your hands off the wheel?