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So my truck has been making this weird buzzing/light grinding sound sort of like a fan or belt rubbing on something. I haven't been able to figure out what it is coming from, I noticed that the fan clutch had lots of play so I changed it. The sound is still there. It happens around 2k rpm but it is not consistent and usually goes away if I let off the gas and get back on it. It is hard to find the sound beacuse of it being so inconsistent so it would help if I knew where to start.
Also check all your pulleys are lined up. My power steering pump pulley was out of whack and making noise. I had to add a couple washers to straighten out the pump and get the pulleys back in plane. Replace the belt/belts while you're there. They're cheap
Look at the fan shroud for any contact marks. My dad's 82 F150 was bad for this, as the body ended up not solidly attached to the frame. Plowing snow made it worse. The column shifter wouldn't go back into Park. At that point, it was off the road and only used for pushing snow around.
Ok so I took a look at the pulleys with your guys advice and found this.
The pulley for the smog pump(bottom in pic) seems to not be lined up quite right with the belt, the belt pulls slightly toward the front of the truck when it moves up to the tensioner.
Is the belt supposed to sit ahead of the lip here or is it supposed to be center like it is? This is the pulley that the fan is connected to.