I've got a 2006 f-150 5.4 XLT. I was having trouble with the power steering and blammed the moan/whinning noise on that. But after changing that out the noise is still present. It gets louder the more I get into the gas. I had a mechanic tell me that it could be the idler puller, belt tensioner, or even alternator that is causing it. I really dont just want to start throwing money into parts until I find the fix, but right now it sounds like crap!! Anybody have any ideas!?

 

Mine had the exact same whine when I bought my truck. Turned out to be the idler. I would start there.

 

If its not the idler, then it might be the bearings in the alternator. I had that issue but its more common when it gets cold.

 

Okay thanks i'll look into that. Did you just replace the idler pulley to fix the whine?

 

Yeah, got it at Advance auto. It was pretty cheap, less than $20 I think. Went on and put a new belt on too.

 

Thanks donbun68 and everyone else. I have a 2010 F-150 XLT 4.6 V8 and it had the engine whine and sure enough it was the idler. Just fixed it. $20 dollars at AutoZone and 20 minutes of time and I am back up and running quitely.