So The other day I started driving and I noticed that my truck was making a whole lot more noise then normal. I noticed that it sounded like the mechanical fan was constantly blowing harder then normal, then I remembered that the fan is on a clutch. I also noticed a drop in performance. I was wondering if anyone has had this issue on their 4th gen and if there is a simple way to diagnose a stuck fan clutch. I think that is what it is.