Steering vibration

[RoyalWapiti]

1998 K1500 extended cab with 165,000 miles.

 

I have a vibration and sometimes a shimmy when at 40 and up. The other day on the freeway it started I thought something broke it was shaking so bad, I jumped at the the closest exit. I could only drive 40mph.

 

In the last year I replaced pitman arm, and idler arm. I bought tierods but my mechanic says no, it's not them. He adjust the steering box when he put the idler arm on, tightened it up and took play out of it. But he cautioned me that you can only tighten it, no backing it out afterward and when the tightness is gone from this adjustment you're done, time for a new steering box.

 

That's what he wants to do. We balanced the tires, found a bad wheel or tire on the rear, but he said that wouldn't cause the front end to shimmy, it would cause the rear to shake.

 

Is there anything I could check before buying a steering gear box?

[RoyalWapiti]

Put new tires on, needed them anyway, appears to have resolved the most of the problem. But also noticed the inside pad on both front brakes are wearing much quicker than the outside.

 

The calibers sticking on the inside may be contributing to the problem as well. They are next.