2003slt

I had a clanging (ringing bell type noise) from front of engine for the past year. Fan does not wobble but I could tell bearing was loose (200,000 miles on this original bearing). Took a 200 mile drive yesterday and noise was severe when got home plus I noticed silver flecks near timing gear cover/water pump. Purchased a KML bearing dac35640037 and installed in fan hub support bracket using large machinist vice. Upon removal the found the large washer and 16mm bolt that mounts to the engine side that couples the fan hub to the inner race of the fan hub support bearing had sheared (the bolt). Looked like the factory overtightened this bolt in on a fan fun nut recall. I could not extract the broken bolt stub from the fan hub so I reassembled the unit with new bearing and left it at that. 1/ the bolt must have been loose for a long time as the fracture was well rusted and the bolt diameter was reduced from spinning around the large washer. 2/ It took a large vice to press and install the bearing and the fan hub adaptor. My question is: what is the true purpose of this bolt (i.e perhaps to make sure the fan hub adaptor doesn't separate from the inner race). I have driven 80,000 miles since this rattling first started which is probably when the bolt loosened and sheared close to back side of hub. It was a bear to drive out hub adaptor from old bearing by the way and I guess this is why the hub never spun inside the inner race or moved out of its original position. The truck had a recall to tighten the fan nut (36mm) to 85ft lbs. I wonder if the dealer over-tightened the fan nut and stretched the bolt as the break looks like like metal pulled apart versus twisted apart. I cannot get the broken bolt out of the hub except perhaps to drill and tap and install a new bolt. Any Input greatly appreciated. Do I keep driving without the hub bolt and just keep an eye out for it?

2003slt

Just to update:
For those interested: The bolt is a grade 12.9 and therefore very hard steel. Some research suggests using a carbide bit to drill out bolt then an extractor to remove the bolt. I am replacing old one with with a grade 10 bolt. Maximum torque on a grade 12.9 M10x1.5x60mm bolt is 45 to 57 ft/lbs depending whether it is lubed or dry torqued. Why Dodge ever suggested 85 ft/lbs is something I cannot determine as Cummins recommends about 45ft/lbs on the hub nut. The fan turns CCW (facing engine) so every time the engine is started or the fan engages the nut is being partially tightened. Oh well, at least it is quiet now and the ringing noise is gone and the bearing should last another 200,000 miles at least.

soulezoo

Thank you for contributing good info for the next person that runs across this issue.