You don't have very much faith in your truck, do you?

 

Well, by spinning - meant to give it a whirl like on the Wheel of Fortune. If it free spins more than 1/2 turn or so afterwards - it probably isn't engaging when it should.

The ones I've had concerns about just about free-wheeled a full turn or more - very little resistance. Have always checked with the engine cold.

 

it has a coupler that engages when it is hot. That way a hot engine will have a spinning fan.

 

Ah, thanks for the clarification. Didn't realize you were referring to just giving it a spin. Your test makes perfect sense.

 

Use a Stant Superstat and go with a Heavy Duty Fan Clutch. The fan clutch will howl like crazy, but it will definitely keep your engine cool. The fan clutch is probably the most overlooked component of the cooling system.