Whiggle, wobble,shimmy dance

#1

no just front end question.

My name is John and I live in Sarasota, FL. I have a 1993 GMC C3500 one ton dually 6.5 l TD with 315000 miles. I use this truck to haul cars as a business, although I am not doing that right now just commuting with the truck. I have a problem in the front end where the steering wheel shakes at 38 + miles an hour. I have had several mechanics look at it; most could not determine what the problem was. One alignment shop said that I need to replace some front end parts, the idler arm, the steering box arm (can?t think of the name), both outer tie rod ends. I have replaced these parts and still I get the shimmy, the steering wheel goes back and forth. I wanted to wait for an alinment till the shimmy went away. I have manually aligned the car it is just a little out (I adjusted the tie rod ends). Recently while going to lunch with co-workers, they were in another car, I asked them to look at the passenger side of the truck to see what was going on they agreed that it looked like the wheel was bouncing. This surprised me, because I had just put on new tires in the front. What could the problem be? I did notice that the shimmy is there when I brake and accelerate, the passenger side does need the have the rotors turned there is a slight warp in the rotor, which shows on the pedal as a very slight pulse.



Here is a short list of what I have done to the truck since 2004



Brakes all twice and turned the rotors

Tires all front twice

Shocks

Outer tie-rods, idler arm, steering box arm.

Upper controller arm bushings.

Lower control arm and all ball joints keep checking out ok.



Thanks



Jack Harrelson

Sarasota, FL

jackatharrelsonsdotcom

#2

When a tire bounces as the vehicle is driven down the road, it’s called wheel hop. And is caused by worn out shocks/struts. I see you replaced the shocks four years ago. So it’s not unusual to have shocks wear out in that period of time.

Tester