1991 Chevy Cheyenne shimmy

MTCAT375

MEMBER
1991 CHEVROLET CHEYENNE
V8
4WD
AUTOMATIC
54,000 MILES

I have a 1991 chevy cheyenne crewcab V series 3500 (fleet) with a gas 5.7l V8. This truck has a solid axle with locking hubs. I had a bad shimmy at around 35 mph. I rotated the tires and replaced tie rod ends, pitman arm and idler arm. The ball joints are good. I had the front drive shaft rebuilt with new U-joints. I cleaned the tansfercase, front and rear diff and installed new oil and seals. The shimmy now only happends in four wheel drive at 40 mph. Do I need to have the camber and caster checked? A friend said he had the same problem and his fix was to add a shim in the rear mount of the leaf spring to bring the caster negative 4 degrees. Does this sound correct?

1 Reply

HMAC300

MECHANIC
48,601 POSTS

If you have replaced all those front end parts, you should have gotten the front aligned. Tires can set off a bunch of things, but by all means get a front end alignment they can check it and make sure it is to specs. And adding shims to change the caster is a common practice. So is twisting the axle on straight axles as one side can be ok and the otherhave negative or positive caster. Also if you have installed large tires, make sure to get dampner for the front end. It helps when oversize tires are installed, especially with shimmies.