Cooling Problem

This not really a cooling problem as my P/U truck ('99 Ranger 4.0L) is not overheating. My P/U however seem to take a much longer time to warm up based on checking how long it will take for the upper radiator hose to go from a cold start to a point where the hose will be too hot to touch (indicating the stat opening up). Could it be the stat or maybe the fan clutch?

Sounds like the thermostat may be stuck open. It's a good place to start your troubleshooting. If a stat is going to fail, better it fail open rather than closed.

Water exits the engine on upper hose. It won't get hot until the motor is hot and thermostat opens. Running the heater will cool the engine.

Also check your water if you have not done so.

The stat was OK but the fan clutch was malfunctioning in that it was not responding to the temperature change. It was not the spring but rather it was the viscuous fluid. Nonetheless I replaced the fan clutch and the temperature control seemed to be OK now.