Bals:

In order to eliminate the spedo I stopped the truck and requested my wife bring the engine to 2,600 rpm and it was evident, I lifted the bonnet and listened to the engine carefully so as to eliminate a valve tap or a heat shield which might vibrate at a certain frequency. It sounded like it was comming from the firewall area.

The whole thing makes no sence because the tach recieves pulses from the ignition coil.....right?

Goofy, but since it stopped it's hard to diognose.

Actually, I believe that each one of these trucks has developed it's own personality in the last ten years or so.

Friends are like that <img border="0" title="" alt="[Big Grin]" src="images/icons/grin.gif" />

Charlie K