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Discussion Starter · #1 ·
Hello - my CS seems to be drifting/wandering down the road when driving (more so at freeway speeds) - driving straight and all of a sudden the car drifts in one direction. Any thoughts on what could be causing this? My tires probably have 3-4k miles left on them. Car has ~20k miles on it.

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Hello - my CS seems to be drifting/wandering down the road when driving (more so at freeway speeds) - driving straight and all of a sudden the car drifts in one direction. Any thoughts on what could be causing this? My tires probably have 3-4k miles left on them. Car has ~20k miles on it.

Thanks
How cold is it when you notice this? Are you driving summer tires under 35degrees F? What tires do you have on?
 

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Hello - my CS seems to be drifting/wandering down the road when driving (more so at freeway speeds) - driving straight and all of a sudden the car drifts in one direction. Any thoughts on what could be causing this? My tires probably have 3-4k miles left on them. Car has ~20k miles on it.

Thanks
sounds like an alignment except that the drift is "sudden". Do you have PTV on the car?
 

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If one of your tires is 'different' (wear, alignment, pressure, diameter, etc) then PSM could be activating and pull the car in unexpected direction suddenly. It happened to me back in the summer when I was on very uneven road, rutted by semi-trucks and the right side of the road was worse than the left and PSM saw a difference in speed and tried to correct it, nearly pulling the car off the road. The effect stayed for the length of the bad road, then went away, not to be seen again.
 

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OP you're gonna need to give more info for anyone to give any kind of reliable info.
 

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Could be alignment, tires, bent rim, who knows. I'd take it to a trusted shop and get it sorted.
 

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Discussion Starter · #7 ·
Car does not have PTV and these are performance winter tires (I experienced similar drifting when the summer Pilot Sports were on the car). Thanks for your help
 

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I've experienced exactly what you describe on local highways over many years and multiple cars. For me it's just the road surface pulling the larger width tires (and thus the car) in various directions. I've raced Formula Mazda with slicks and the road surface will try and rip the wheel out of your hands due to differences in grip between the front tires. So.....I would vote it's likely more the road itself than your car.

That said....always better to be safe than sorry...so any doubt in your head...go take it someplace to check your alignment and general condition of your suspension.
 

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Probably normal.

My experience with my Boxster is when the tires are nearly worn out the car gets real squirrelly to the point I've actually left the freeway to check for a low tire. The last time the car was particularly bad at this and I was thinking that due to the miles on the car (around 280K) the suspension or steering was just shot. But a new pair of front tires -- the old ones had more than 40K miles on them and were actually nearly to the wear bars which is quite a bit more worn than they have every been allowed to get before -- eliminated the behavior and the car is nice and stable and not wiggly/squirrelly any more.

Still you should check tire pressures. Make sure none of the tires is under inflated. My experience over the years is tires are more prone to picking up a puncture when they get close to being worn out. Make sure the tires are not overinflated and that the tire pressures on the tires on the same axle are the same. I use a precision tire pressure gage that allows me to get the pressure within 1/2 psi.

Feel the tread surface of all 4 tires. Feel for feathering or other signs of tire misalignment.
 
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