The speedometer when awry on this truck yesterday. It froze at 65 mph while driving. Then after a few stops it began to wander from 50 to 120 mph. Now it generally stops at between 35 and 55 mph with the vehicle stopped, and freezes there when the engine is turned off, without returning to zero. This is one of the "dial" type speedometers, and all the other instruments -- tachometer, engine instruments, odometer -- work fine. This happened on a cross country trip last September, but it fixed itself after a day or so.
Does anyone know where the speedometer sending unit is located? I assume it is on the transmission, but is it top or bottom, left side or right side?
This sounds like a broken wire/ground problem to me, but any ideas would be appeciated before I take it to the Chevy house. Thanks in advance.
-John Banister