I don't know what's wrong with your tank monitoring system, but it DOES sound a bit like a bad ground somewhere.
As far as tank probes go, I replaced all mine in the grey and black tanks with Horst Miracle Probes and have been very satisfied with the result. They were not too hard to install. I had tried cleaning the tanks with the old probes, but they still gave false high readings. The new ones don't.
Hi-Lo 1707T - Tire Minder TPMS on Tow Vehicle and Trailer, 300W Solar Battery Charger, Equal-i-zer WDH
2014 F150 Platinum 4x4 3.5L EcoBoost SCrew