Those tensiors are a *****.... You definatly have to take the smooth idler off first then remove the tensioner... I think its a 12-14mm socket range... All the new tensioners whether ford or napa or oreillys have a larger pulley than before. Don't ask me why i have no idea lol.. But when you install your new tensioner use a 1" large belt so the marks on the tensioner line up... Other wise using the factory size belt well cause to much tension and you will be replacing them every 3000 miles like i did before i learned.. Here's the belt part number that is the correct size from carquest: RBR K061120... They call it a micro v belt... I'm sure it cross references to any other brand... If you have a non turbo idi 94 this is what you need.. I believe the 93 and older trucks were still V belt not serpentine.... 94 idi turbo's have a small shock on the tensioner
