What can stop my car from shaking? 2012 Impala on 20 inch rims
Are the rims bent? Did you have the wheels balanced recently? With bigger wheels and tires, you can introduce more vibration. Have it looked at by an alignement/tire shop.
Sounds like a rim in the front is bent. Make sure there isn't any play in the steering components but as sounds like a bent rim if you can feel it at 20. Maybe you get lucky and just have a bulge in a tire
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