Temp Rising on 00 4.7 Dakota Help!

I have a 2000 4.7L (150,000 miles) that the normal operating temp is going up. The temp has stedily climbed from 180 or so to about 220 over the past few months. When pulling trailer got close to overheating. No past problems when trailering. Recent repairs include radiator flush, thermostat, hoses, fan clutch, trans flush, timing chain and cover. There are no leaks, water/coolant and fluid levels ok. I think the water pump was replaced w/timing chain cover, but not sure. Any ideas out there? What could be the problem?
Thanks

coolant sensor sounds bad or could be the a/c compressor sensor... have those checked out or have someone do a diagnostic an u should have ur problem solved - u can get a self diagnostic computer from a parts store for about 150 bucks - works foor for 1994 an up - OBDII connector cars.... check one of those out - it saves u alot of money in the long run plus u can have people pay u to check there cars for them... I do that i check an fix for people all the time.

Good Luck

Matt