ok, lets see if i can discribe this thing cause i have no idea what it is. its in between the radiator and the oil cooler or the other radiator thingy,anyways its kinda lika a cable or harness of some sort,it goes through the two radiartors and kimda ends in the middle of the radiator,it has like another line that holds it there,well theres a grinding noise if you ,listen right in front of the grill,i can get to it to tighten or service,but i dont think you can tighten it,my truck is a 03 dodge cummins,5.9l, 4x4, 2500,ive went through my book and cant find anything on this part,anyone that has an idea what this irritating grinding noise can come from please let me know. ive owned this truck 5 years and not a problem,it runs and all just want to end the noise.thanx

 

Power steering cooler probably.

 

I am probably way off but when the truck is cool, and you spin the fan, can you hear anything? Does it spin more than five times? Just wondering if it might be your electronically controlled viscous fan drive wiring harness that connects to the fan drive pully. Though the wiring for that on my truck comes up from the bottom so I am probably way off.

 

Ref your PM about your fan wiring:

There was a really good post on this awhile back but now I cant find it. Doing a search for “fan clutch wire” turned up these.

https://www.dieseltruckresource.com/...light=fan+wire

https://www.dieseltruckresource.com/...lutch+wire+cut

https://www.dieseltruckresource.com/...lutch+wire+cut

https://www.dieseltruckresource.com/...lutch+wire+cut

If I can find the one I am looking for I will send it to you.