I have a John Deere 5425 with cab. I can run the tractor all day under load without the AC on and no overheating issues at all. I can turn that AC on and I can start watching that temp gauge slowly go up until I have to turn it off. The temp will return to normal. I have made sure that the radiator and AC condenser are cleared every time I go to the field. What am I missing is the fan system inadequate? Is there aftermarket improvements I can do to the cooling system. It doesn't stop me getting finished what I am doing but at that point an open bay would be cooler than me under glass. TIA