I took my truck for our first real road trip after installing the Ole Smokey mount, and she ran great untill we were on the way home.
I started hearing a high hum or whine from the engine around 3/4 the way through the trip. It would start, make the noise for a few seconds(10-20) then it would stop. there was no change in rpm per the tach, and it happened while going uphill, downhill and on flats. All the fluid levels were good, and the air intake hose was intact and in place. I could find nothng wrong at all, and noticed no change in performance.
The noise was exactly like the noise one of those electric cooling fans makes on little imports when they kick on, and lasted about as long as well.
I checked the fan clutch and it seems fine.
I did find a leak in the the A/C system, but the noise continued to occurr after shutting off the A/C..
I did notice that it seemed to happen in the 65-70 mph speed range but not at one specific speed, and slowing or accellerating did not correct it.

Stymied about it, any suggestions?


Oh... and my headlight switch went out on me about 20 miles from home, right at sunset... headlights/brakelights worked but no tail/running or trailer lights....

 

It may be the fan clutch locking and unlocking. Since it happend up and downhill, it makes me think that maybe the clutch is getting tired. Check it for any obvious play. Sometimes they die unlocked and sometimes they die locked. Sounds like yours is trying to decide which way to go
g

 

sounds like fan clutch

 

If its the fan clutch, shouldnt the clutch freewheel when I first shut off the engine?
I was always told that is the sign they are going out.
When I shut down, it stops immediatly...

 

Yes, it should continue on for a revolution or two. That clutch sounds pretty ticked off. If it's froze up solid, there won't be any bearing play to be felt cause they melted and welded themselves together! If that's the case, the fan could overspeed. Best case is the fan comes halfway thourgh your hood and doesn't hurt anyone....better take a closer look. JMHO.
g

 

Ok thanks guys... I will look at replacing the clutch.