Engine cools fine but at 70 mph there seems to be a roaring noise under the hood and gets louder the more you press the gas. Could it be the fan clutch is engaging at those speeds and that is what I'm hearing? The fan turns at idle and seems to draw air and with the engine off, has some resistance when you try to spin the fan by hand. I've got about 41k miles on the truck.

 

see if you can reach in there with it running and stop it with a rag or something on your hand. if it stops fairly easily then yes you have a weak clutch...... I have the one off of my truck if you need one it only has about 14k miles on it...

 

Is that really safe? Or is there another way to check without losing some fingers...?

 

if its bad it will stop, with little to no effort, or you can try idling the truck then shut it off, and watch the fan see if it still turns after truck quits running

 

I personally wouldn't go sticking my hands near a turning fan

From the way you describe it, sounds like the clutch fan is doing it's job...as for the roaring on the highway, maybe you have another issue like a wheel bearing or exhaust resonance or something?

 

[QUOTE=budhayes3]I personally wouldn't go sticking my hands near a turning fan



It doesnt hurt for long, but yeah its gonna make some noise!!!

 

I'd put money on your clutch being bad. My 98 Sierra had a bad clutch; at full throttle you could almost hear the fan over the exhaust, it sounded like a vacuum cleaner coming down the street and was annoying as hell. The damn thing would never disengage so the fan was constantly spinning.

 

Thanks for all the feedback. I'll probably go ahead and change the clutch. I wish I could go the electric fan route but funds are tight right now, but I'll eventually get there.