Symptom: Temp sensor in MagHytek on the rear axle is erratic. It bounces between 0 and 180 or whatever. Step on go pedal and it reads 180 (whatever), let off go pedal and coast and it reads 0. Throughly ticked me off, tried several things before just laying down and studying the install.
There is no ground to the diff, apparently the ABS sensor is isolated and the springs are rubber mounted. The only ground I could see is through the driveshaft
and it wasn't a good one.
I put a self tapping through the bed mount and attached a wire between there and the MagHytec. Problem solved. Gauge reads steady now ( anyone need a 300F sender, used for 5 minutes :{ )
There is no ground to the diff, apparently the ABS sensor is isolated and the springs are rubber mounted. The only ground I could see is through the driveshaft

I put a self tapping through the bed mount and attached a wire between there and the MagHytec. Problem solved. Gauge reads steady now ( anyone need a 300F sender, used for 5 minutes :{ )