Author: NecroFile  <...>    76.90.114.55 Use this link if you want to link to this message and its entire thread of discussion. Post a Msg
Date: 9/9/2017 11:57:08 AM
Subject: RE: more ford

its definitely uncommon on a half ton truck

the fan has two modes of operating,
one mode is normal where the fan is driven by the engine belt,
the second mode is where a clutch engages and causes the fan to rotate 3 or 6 times more than it normally would. its very loud and you can feel it taxing the drive belt, similar to an AC compressor