[deliriousga]

What's the mileage on the car?

There are so many things that can cause it. I'll start with the easy ones.

1) Clean all of the ABS sensors with brake cleaner. They can collect metallic dust from from the pads on the magnets over time and then they suddenly can't feel the wheel moving. They can freak out thinking the wheel is locking up since the speedo says 85mph and the sensor thinks the wheel is not moving. It starts to pulse to unlock the wheel and you feel vibration. When mine did this, it was over 80mph and as I went faster it got worse to the point where it was shaking really hard.

2) Out of round tire.

3) Worn A-arm bushings. Not a good one since you have to replace the whole arm. They don't sell the bushings separately.

4) Bad wheel bearing.

Just a few I can think of off-hand.