Hi I have a 2001 ford ranger edge with a 3.0 v6 in it, about 4 months ago my belt started squeaking now I’ve done a lot of research and come to find out this is quite common. The first go I had at this was my idler and tensioner pulley, for the record it was just the pulley on the tensioner not the actual tensioner, after replacing both pulleys and throwing in a new belt the squeaking stopped. Problem solved. Well my radiator is junk, rusted out, so I did what any man would do and flushed my radiator of all the old rusted coolant, unfortunately the coolant got all over my belt and pulleys and the squeak started up again. And this marks my decent into madness. I thought the belt was covered in coolant so I sprayed the engine bay out to clean it all off and the belt still squeaked, so I sprayed wd40 on the belt and the squeak stopped for like 30 seconds. So I started diggin into the belt system and I found that my alternator pulley was squeaking, so I replaced the alternator even tho the old one was brand new. The belt still squeaked, so I ran to the parts store and grabbed the second best thing I could think of, a new tensioner, I threw the bad boy on there and the squeak stopped…. Until this morning, when I started it up and the squeak was back not as bad, it is very quiet now. So now I’m running out of options, today I took the idler off and sprayed the bearing with some wd40 because that is where to me the sound originated from, I started it up and the squeak was gone until I revved it and it started back up again. So at this point I’m thinking either my belt is bad from all the coolant and wd40 that’s been in my engine bay or the idler pulley bearing isn’t lubed enough. I’m at a loss here. Every pulley in this drive system is new except for the ps pump, the ac pump, the fan pulley and the actual drive pulley off the crank. I need help.