How can I tighten up the steering on my 68 chevelle. If I hit a bump in the road and the steering moves the slightest it throws me around. There is a lot of play in the steering. I recently acquired this car and I am not sure how old the steering box is. Any help will be appreciated.

It's more likely to be the linkage than the box--although it could be both.

I'd be inspecting the ENTIRE steering and suspension system, from the steering column to the tires--and including the control arm bushings.

Thanks I will do just that. I was not sure if you could adjust the box itself or not. Maybe time for a suspension upgrade.

Play can come from many places...

If there is play in the box, there is an adjustment that may reduce it. The an adjuster bold over the top of the pittman shaft. This bolt adjusts how high the shaft can go, and since the gear teeth on this shaft are tapered, high is looser and lower is tighter. I would look up an official adjustment method in a service manual for this one as you do not want to go to far.

The other item to consider is that these cars typically had NO caster or even NEGATIVE caster. Both of these increase the disturbance factor on the front suspension. Get a front end alignment with as much positive caster as they can get and still have match from side to side.

A good general checkout is always a good idea.

Get the front wheels off the ground and have someone grab one wheel at 3 & 9 o-clock and rock it back and forth while you are underneath the car watching for play in the steering linkages. I grab each steering joint by hand to feel the play better. Then grab the wheel at 12 & 6 and really rock it to see if you have ball joint wear. Odds are that it has a little ware in each joint if one is not totaly shot. I would put in a whole new front end kit and be done with it.