Hello, I recently purchased an 89 K5. When I drive over a series of bumps (common for Mi. roads nowadays), my truck sometimes starts to shake left and right until I slow down. It feels like the front wheels are being turned back and forth quickly, but I'll be holding the steering wheel completly straight. If I speed up, it becomes more violent. If I slow down enough, it stops and then continues to drive normally. I'm going to take off the front wheels tomorrow to have a look. Please write back with any suggestions or comments on what I should look for. This forum is always a big help, thanks.