Ours also had off road tyres, but when a way and out and about for th day probably did less than 100 miles on any one day. Internals fitted to caravan can be expensive and you still ned an additional monitor. Remember on the caravan you do need to deflate and inflate the tyres constantly. We go months without having to pump the caravan tyres.yes, I do use the Shogun which is fitted with proper offroad tyres, not the soft road Dunlop rubbish it was built with, and they make for a harsher ride when the car is empty and the tyres are inflated to towing pressure. So, when I go away for a short break its a real faff undoing locknuts and then trying to unscrew the sensor before I lose 2psi. Im not decrying the system and when I change the car it will have internal sensors and I will have internals fitted to the caravan.