I've got a 94 F150 XLT 4wd, Auto, Ac, etc.. I took the pulley off of the smog pump and was reading a previous post that mentioned getting a 94.5" belt, and when doing this I would then bypass the pump and not use the idler pulley. Belt fits as diagram showed, but, man this thing squeals like mad.. Was I led in the wrong direction with the belt size and routing? I've also read posts on here where they used 89.5" belts and routed differently. I know there is a kit, but, just trying to get the old pump was a pain..

 

Sorry, not sure what happened to the double message.

 

It sounds like the belt is either to tight or to loose. I know when my ac froze up I just measure the distance around the pulleys and bypassed the ac pulley and got a belt according to the length and ran that. I'm not sure if that helps you but that is where I would start.