i have a 99 5.4. when it is cold outside and i start my truck in the morning, there is a squeaking sound. i have heard that it might be the belt tensioner. it goes away after about 5 minutes. any ideas of what it might be?

 

My 4.6 does it from time to time in the cold always figured it was the belt or one of the pulleys.

 

Could be the belt, the belt tensioner, or possibly the fan clutch. A thermo-type fan clutch is nothing more than a fluid coupling. If the fan clutch is bad and leaked all the fluid out or maybe if it was cold enough the fluid is actaully thick and the 5 minutes is enough to thraw it up enough to silence the squeal. I might be way off base, anyone else care to disprove or improve on my idea.

 

I have had problems with squealing. I've had the belt replaced a couple of times, and tensoner, ildlers. I finally stumbled upon the noise by taking the belt loose and turning all the accessory pulleys by hand.