So the steering on my 1999 Blazer with 109,000 miles has the usual play in the steering. There is no play or wear on the linkages connecting the box to the wheels and I adjusted the adjustment screw on the actual box. The adjustment stiffened the feel of the turning wheel but did not take the play out of it so I loosened it back up a bit. The shaft leading into the steering box can turn about 1/8 of a turn without translating into any output from the steering box. I am assuming that the whole box is going to need to be replaced. Am I on the right track or can something inside be rebuilt? Thanks ahead of time for any help.

 

I have never seen a steering box go bad with 100,000 miles on a GM product ever. I have been around a long time. Ford, YES, GM, Never, unless it has been wrecked (front end). You need to check ball joints & bushings in the A-Arms etc.

 

rag joint in good shape?

 

The rag joint seems ok. There is very little play in the joint. Basically more or less 100% of the motion that happens in the steering column transfers to the steering box. The shaft rotates about 1/8th of a turn but this translates to 0% output from the steering box. I adjusted the allen nut on the top of the steering box and this did not remove any play. Are there other adjustments that can be made internally on the box?

 

As I said I have never seen a GM steering box go bad. You proved it If by adjusting the Allen screw if that didn't take out the ply yet the steering tighten up the box is OK. You need to take it in to a front end shop & have it checked.
I worked for GM dealers in the day so I have been around for a few days. I was also ASE certified in front ends.

 

I always thought that allen screw was for adjusting the return-to-center ability of the box and was told to leave it alone. A guy I know of actually had a ZQ8 box lock up while driving after adjusting his. He was trying to get rid of the extra play, also.

 

How did he end up fixing his steering? From I have gathered, tightening that nut pushes the gears together and is supposed to help get rid of the play.

I checked out the undercarriage again to make sure I wasn't missing anything. Had the wife turn from full left to full right slowly while I sat under the car and watched everything. Definitely no play in anything connecting the wheels to the steering box. All of the play is in the steering box. I know you said that they don't usually go bad but unless there is another adjustment to make to the box that has to be what it is. I only adjusted the hex nut on top. I did not tighten or loosen anything else other than the lock nut on the hex nut. Is there something I am missing? If not it's off to pick up a new steering gear in the next few days.

 

Aren't the ZQ8 boxes a quicker ratio? Maybe you could swap in a ZQ8 box.

 

Not sure what that is.

 

Have you checked for any play in the 'pitman arm'? I replaced mine and it seems to have taken care of my issues. I got mine from the parts store for $50.00.