Since the day i bought my trackkick as the trucks engine reaches operating temp the water temp gauge climbs up to and then stays in the center...which i assume is the normal position it goes into while driving.  It's done this without fail for 6 years now.

2 months ago it started doing something else.  It goes to the center once the engine warms up...but now when i accelerate it drops down.  If i'm on the highway, it stays near the cool area of the gauge.  When i come off the freeway off ramp and slow down it climbs back to the center.  And when at idle it stays cetered.

This thing is bouncing all over the place.  Is the gauge toast?  or is it something worse it telling me that i should be looking at.  The truck runs fine, not anything wrong, or any odd noises.  just the guage bouncing.

Most likely you have a bad ground connection somewhere under the dash.

I've seen this on other vehicles and what usually happens is with the instrument panel ground missing or loose, the gauges ground through the speedometer cable, and as that rotates the "quality" of the connection varies - with the vehicle stationary the gauges read approximately normal and with the vehicle in motion they go crazy.

I cleaned up the connections from the sending units (fine sand paper / emery board) - cleared the problem right up. I wasn't sure which went to the ECU, and which went to the gauge, but both were corroded, so I just did both of them.