Joined: Nov 2016
I'm not sure about the 79 specifically, but many times the 2 piece collapsible columns use plastic spacers inside that can get brittle and fall apart, or the sliding joints get sprung when the wheel is twisted too hard. When that happens, there's play between the bottom part of the column, and the wheel.
If you mean the box itself has play, as in "i can turn the input shaft on the steering box, but the wheels don't move", then this is probably a problem with the steering equipment. If I recall correctly, that year's got rack and pinion doesn't it? Which means the teeth on the rack are probably worn down, especially in the middle, where you spend most of your time driving. You could test that by steering to one side or the other and see if the play decreases. If your rack's shot, replacement is the solution.
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