The speedometer in my truck is horribly wrong and seems to be temperature sensitive. I have a 1994 Ram 1500 4x4 with the 46rh (a518) automatic. For the first fifteen minutes of driving my speedo is about 30-45mph inaccurate. I know because it read 35 when the state trooper clocked me at 72. As the truck warms up it gets more accurate though never within 10 mph of right. i'm only running 33's so i don't expect tires to throw me off more than about 5mph and definetely not a variable difference. My question is would the speed sensor be more likely than a problem with the gauge cluster? Or is it possibly a short in the wiring somewhere?