Chevrolet Repair: 2.2 S10 overheating, losing coolant, radiator flush

Question
I have a 95 S10 2wd 2.2 that over heats under normal driving if I don't run the heater. I replaced the thermostat and it is not losing any coolant. I have noticed a "very" slight loss of power. If I drift in neutral down a long hill it cools down. I'm thinking clutch fan or need of a flush. My fan does not seem to have any play in it but i was told that it still may be bad. I would like to avoid replacing good parts if possible.Any info would be appreciated. Thanks.

Answer
Well the fan clutch would be my first guess. If your not losing coolant that tells me that you don't have a gasket problem(usaully head gasket is the culprit). If you open the radiator cap and it's not too nasty then radiator flush probably won't help.