Hello. I have a 2008 focus s. recently the temp gauge climbs up to hot. just started happening out of the blue. I flushed radiator, put new coolant in it. I have great heat coming from heater, if i drive it with heat on low its fine in the city, on the highway after about 20 minutes it starts climbing, seams to b getting worse to were i've had to have heat on number 2 setting to keep it at normal operating temp according to gauge. radiator fan works fine, both heater hoses as well as top radiator hose gets pretty hot, hence i dont think its the thermostat. engine dont seem hot nor do's radiator cap, I can easily touch both. Radiator dont seem plugged, i can gently squeeze lower hose and c coolant move up and down in radiator. I have no coolant leaks. any thoughts? thx in advance for your helpful comments......