85 2.8l 4 speed

betweeen 55-75 mph i get a steering wheel shimy(right to left movement), anything above is rock solid. the shimy will somewhat go away during curves on the highway. i balanced and rotated the tires, no diffrence......... car drives striaght, steering wheel is level........ any ideas


im just tring to fix one problem at a time with this car i got a list a mile long............ thanks for the help p.f.f.

chris

shimies are usually do to either alignment or out of balance tires . If it was the steering rack one would think it would happen all the time.

Even with a worn out steering gear or rack, a front shouldnt vibrate. Its either bad wheel balance, out of round tire, or bent wheel . Place I once worked for had a big delivery van. Driver was on the freeway and felt a big thump. kept driving till the next exit and pulled off where it came to a screeching stop. Tie rod end had fallen off the spindle on the ground and still wasnt any shimmy till he slowed. We figured since he was going at speed, gyroscopic action kept the wheel pointed ahead till he slowed down and it pulled outward all the way.

Wal-Mart forgot to balance one of my rear tires, the dash board shook violently--as did the steering wheel .

if it goes away in curves, it may be a ball joint or wheel bearing. this usually also includes some braking shakes - which feel like a warped rotor. look at the tread of your tires - especially on the inside edge, and feel for "cupping" - which is an uneven repeating pattern.

A static wheel balance will not correct a shimmy (usually from 50-70MPH) if the imbalance is not in the plane of the wheel. i.e. the wheel/tire assembly is heavy at the outer edge of the rim in one spot and heavy at the inner edge of the rim at a spot approximately 180 degress away from that. The 180 degree offset is worst case. If you didn't get a dynamic wheel balance, I would recommend one.

thanks guys for the input, i have weights on the inside and out side of the rims, is the the dynamic wheel balnce, also i have a one bad upper control arm bushing that i think is the culprit. I moved the tire with my hand at 12 and 6 postion and the steering wheel moves, are thses hard to change out it looks awfully rusty like 20 years worth......

If the weights on the inside and outside of the rim are at about the same location, then the wheel/tire could still only be statically balanced. A dynamic balance results in the inner and outer weights being on opposite sides of the rim, i.e. diametrically opposed.