I've been meaning to ask about the mechanism behind a developing issue related to the steering column on my 94 pickup. For some reason when making 3-point turns or the like and rotating the wheel through its range, it most noticeably exhibits a developing sound reminiscent of wearing new boots or the twisting of a rubber band and sometimes a humming. It sounds like something would eventually sever or fail, though after months of this, drivability has not yet been affected. The one problem that seems it could somehow be related is every so often the speedometer remains at zero for the first few miles of a trip.

 

First off, your two issue are not likely to be related.
next, where is the noise coming from? steering column? outside where the tires are touching the ground? under the hood?
finally, if your speedo is cable driven your issue is pretty much 100% the gauge itself. If it is electronic then you have a few things to check with a voltmeter and wiring diagram.

 

The noise is coming from the column inside the cab, close to where the wheel meets the trim.

 

If you can't figure it out try replacing everything attached to the radiator cap