Bring it in for a re-balance and alignment check. There may be an issue with a tire, balance, toe angle, tie rod, ball joint, or a wheel bearing. Someone will need eyes and hands on it to determine the cause.
Sorry I didn't explain fully. New tires, rims, hubs, control arms with ball joints, outer tie rod ends. The new tires are toyo extendza 2356016 balanced 3 times and alignment twice. I had 2256016 which is the oem size on there originally but I was told that one inch wider tire wouldn't make a difference.
Ah, the wider wheels/tire setups tend to require some extra care to align properly, since it's slightly different geometry than the OEM setup. The extra 10mm tread on each side, and any change in offset of a different wheel can require slightly more care for the alignment than just being within the generous +/- limits of a factory setup listed for the car.
I'm running a completely different setup on my Regal that started with the same 225-60-16's, and now has the 99-04 Mustang GT 17's with 235-50-17 tires offset further out. It behaves normally only because the shop (thankfully) got it right.
Maybe, depends on how much how much adjusting was applied since swapping. They should be able to get the new stuff right, otherwise the original parts should go back to normal. If they're going by computer readings-only, and not putting the effort in to ensure it's correctly working afterwards, I'd consider a different shop.
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