Rattle, ticking noise at idle
 

2006 6.0 / 120,000 miles / 2100 Hrs

Just an FYI for those that may have searched this before and found not much on the subject like myself the past few days.

I started to notice a ticking or tapping noise when my truck was warm sitting at idle. You could faintly hear it inside the truck and at the drivers side door. Really had me nervous because when I searched this topic on google I saw a few mentions of a lifter or valve train issue. I popped hood and tried to listen and look. Truck has original water pump and I noticed what appeared to be some wobble in the pulley while spinning.

Seemed like the sound was resonating through the aluminum intake manifold. When I put my hand on top of the intake elbow you could feel a tapping, but none on top of oil filter or turbo housing.

So I tore into it yesterday. Pulled radiator and fan assembly. When I tugged up and down on the pulley for the water pump there was enough play to make that same sorta tapping it was doing. I think this is from having enough play in the shaft that the impeller contacts the inside of the water pump housing. So I went to Ford got some new parts.

While in there I had 2 pulleys with excess play as well and a new alternator I just put in from Napa with bad bearings. So 2 new pulleys, belt tensioner assembly, and alternator.

Buttoned it all up and she is good to go! No more tapping.