Took a trip to southern Cali (from Seattle) last week loaded with camper and EB on trailer. When going up passes and had to downshift out of OD (above 2700 RPMs)I heard a loud squeak/screach, like a fan belt? But after a few time it would only squeak when the cooling fan was on. As soon as the fan shut off the squeak would stop.
The other funny thing was when the fan was on it would occilate between fast and slow. I could hear it slow down and speed up about 4 or 5 times.
Would this be a fan clutch going bad? Ford dealership could replicate the conditions so they said nothing was wrong /ubbthreads/images/graemlins/rolleyes.gif