2003 Oldsmobile Alero overheats with a load, runs normal in

Water pump cracked, took to a shop and had it replaced. Car started having a whine like an rc car and a week later check eng light came on. Brought it back every week for a month. They claimed to be adjusting the thermostat. Ha ha I know. Finally gave up and ran it with the light. It ran cold. Finally got back to the problem 3 yrs later. They cut the thrmst. Replaced it car overheated only with a load ran fine in park. Replaced radiator, water pump, coolant. Bled system with compressor and suction tool. No air in system. Car still shows same signs. No milkshake, no gases in coolant, no leaks, hard hoses, hose to radiator cold, hose from radiator hot. Help!