I have a 2000 F150 5.4L 4X4. I am having an issue with a squeaky pulley. My Belt is only 3 months old. How can I diagnose which pulley is the issue? Also I am not sure if this is correlated but my external temperature gauge for the past few months has been off by 10 to 12 degrees on average, and then all the sudden this week it has been 60 degrees off. Today it is about 35 degrees and it read 90 degrees F. I'm hoping my water pump isn't going and throwing off the external temp by adding extra engine heat. Is there any correlation between the two? Thanks for the help.

 

Use a long screw driver and carefully put the tip of the screw driver in te bolt holding the pulley on, then put I rear to the handle end of the screw driver. You will hear which one is bad. My vote is tensioner pulley.

Also btw, as for your external temp gauge, make sure the wires aren't cut and the sensor is clean. It's located on the drivers side core support jut right of the hood latch iirc.

Wayne

 

What does.ur temp.gauge in.side.cab say.look.for.anitfreeze flow remove cap from radiator if.there is.no.flow.it will b water pump but like he said above possibly tensioner pully or idler pully

 

Thanks for the help. I replaced the belt tensioner it sounds better but still has a squeak. As far as temperature the coolant gauge reads in the middle between high and low. Although I never really drive far enough for the temp to climb if it was going to.

 

I also just replaced the idler pulley still have a squeak. the squeak at Idle went away

 

Alternator bearings?