i have a 2000 grand pix gt the left front tire vibrate real bad sometimes an when u got alot of people in the car it does it worse
Have it inspected by certified technician. Could be as simple as a tire out of balance. But could also be a wheel bearing, tie rod end, ball joint, cv axle or strut. Any of these last listed could cause serious injury or death if they come loose completely while you are driving at highway speeds.
Agree with dandyoun. And I would be inclined to say it is most likely the front axle shafts. Consider changing the front bearings at the same time.
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