Hello, new here, but had a question. I have a 99 Sierra 2500. It has a 7.4l 454 engine. I notice that when I an in idle or parking the 5th wheel, my temp will stay at or just below 210. Once I give it gas or get going, the fan kicks on. Shouldn't I hear the fan in idle too. I'm thinking the clutch fan or relay switch not working. Our is this ok?