Belt Tension
www.1aauto.com shows you how to replace your worn out serpentine belt tensioner and idler pulley on one of GMs most popular set of truck engines ...
13mm nut. Fits any 13mm or even 1/2" tool that you might want to use.
complete unit, same lenght as the factory tool
rounded and smoothed end, no damage to tensioner shoe and easier threading into the block