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Fan noise

2003 trailblazer automatic, 4x4, with 107k, in morning it sounds like the engine is going fast but its not but transmission was checked out and its OK! someone said it was clutch fan is that true?

Your description is a little vague, but yes a fan clutch can lead to excessive noise. It won’t hurt anything though (to the best of my knowledge).

Do you have a tachometer? What does it read in the morning when you hear the engine “going fast”?

The problem might be with the fan clutch. When the engine is cold open the hood and try spinning the fan by hand. It should spin at least one revolution. If not, the fan clutch is defective.

Tester

When the fan clutch locks up, that will contribute to overheating at higher engine speed, at least that is what my old dad once told me. Nothing desperate, but it is not an expensive part, and should be replaced if defective.