Since I bought my '87 GT I have been trying to fix all the little problems and stop the little annoying rattles. Last week I was down to the last rattle, and it seemed to be in the instrument panel. I could hit the steering column and hear the noise (every sharp bump I drove over also resulted in the same noise). After searching through the instrument panel, I started to fear that the problem was deep inside the steering column (it has the tilt wheel option).
I decided to pull the steering wheel and 'look' for a possible trouble spot. Boy did I see the problem. The steering wheel is held to the hub with six short screws. All but one screw was loose! I think that the only thing that keep the screws from falling out was the plastic trim that the horn cover sits inside.
I drilled out the 4 alum rivets that hold the plastic trim pieces together. Then I removed each screw, applied a little red lock-tight and screwed 'um back into place. The rattle is now completely gone and the steering feels very solid with nearly all the play gone.
If any of you have a little rattle right in front of you, you might want to remove the horn cover (it can be pulled of with your fingers) and inspect the steering hub for any looseness. You will see a number of metal fingers that point toward the driver. Move the wheel while your watching these metal pieces. If the steering wheel moves in relationship to these fingers, you too may have few screws loose :)
From: Lee Brown