Fan Clutch Unscrewed Itself

[Tractorman]

My brother-in-law moved his 2003 2500 4wd NV5600 truck yesterday. While he was moving it, I noticed a ticking sound coming from under the hood. Upon investigation we found the whole clutch fan assembly laying in the bottom of the radiator shroud. Not what I expected. The unit had unscrewed itself from the threaded pulley hub. The interesting part is that there is hardly any damage. The large clutch fan nut shows witness marks where the outside of the crank pulley was rubbing and two fan blades show similar wear from rubbing on the crank pulley hub. The fan blades never contacted the radiator or anything else (including the fan clutch thermal switch and wiring harness), which was amazing.

So, I am thinking that maybe the fan clutch was locked and the assembly came off when the engine was shut off; otherwise, I think the damage would have been much more severe.

Anybody ever had this happen to them? We replaced the fan hub bearing in December, 2018, just over 20,000 miles ago. I used the proper wrenches to remove and reinstall the fan clutch. Most of my life I was a mechanic by trade and I have been around Dodge trucks and many other similarly equipped vehicles and I have never witnessed or heard of this happening.

A new Mopar fan clutch and a new Dorman fan have been ordered.

- John

 

I just realized I posted in the wrong forum.  Should be in the third generation powertrain forum.  Maybe someone could move this post.

 

Thank you,

 

- John

Edited October 12, 2021 by Tractorman
posted in wrong forum