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A friend of mine brought me his 2011 f150 with the 5.0 to check out an engine knock. The knock is coming from the lower end maybe even the transmission. I found the TSB for the the AC belt replacement and tensioner and thought that might be it. So he took it to the dealer and they said the noise still is still there even when the belt has been removed. They told him it is normal and not to worry about it. They said even if they break the motor or tranny down they might not be able to pin point it and it will cost him a ton of money. So $50 later for the diagnose he is getting his truck back with a knock at idle that they can't tell him whats causing it or how to fix it. Any thoughts?
I had a 2013 with 17k miles that developed a similar knock. Could hear it at hot idle, best heard through passenger side wheelwell or from underneath the truck. I traded it. Not sure if it was going to be a problem or not, but I didn't like the sound being there with such low mileage.
Since your friend's truck is out of warranty, there's not much he can do other than run it until it breaks, or trade it off. Heck, sometimes there's not much else you can do even if you do have a warranty. lol
I'm assuming the sound was similar to mine since it occurs at hot idle like mine did.
I have sililar sound but it is a bit strange. It only happens occasionally at hot idle and it is intermittent while making the sound and some day it doesnt make it at all. Mine is a '13 with the 3.5 ecoboost. The sound is almost like a drummer that is off beat or a gurgling sound like a hot radiator ?
Sirikenewtron did you ever find out what your sound is? Mine is similar?
I have sililar sound but it is a bit strange. It only happens occasionally at hot idle and it is intermittent while making the sound and some day it doesnt make it at all. Mine is a '13 with the 3.5 ecoboost. The sound is almost like a drummer that is off beat or a gurgling sound like a hot radiator ?
Sirikenewtron did you ever find out what your sound is? Mine is similar?
That's a good description, a drummer that's off beat.
No, I took to the dealership and of course he couldn't hear it but to be fair it is kinda hard to hear unless in a quiet area.
Mine also only dose it after truck has been up to temp for a while.
Truck drives strong and fine so I figure I'll just keep an eye/ear on it.
Mine does the same thing you describe. When it was still under warranty every time I tried to take it in when it would do it, the sound wouldn't reappear of course so I gave up and figure if it was something major, it wouldn't still be running. Have 70k trouble free miles thus far so I just learned to deal with it. Sorry this wasn't helpful in anyway.
I just went though this with my 2013 5.0, the first four trips to the dealership I was told it was normal, the fifth time I had a friendly chat with the service manager about my concerns and also politely informed him that I would not hesitate to idle the truck right in front of their new truck lot with a sign in the window, and post videos of the engine running on social media. Now, two weeks later, the noise is gone. It turned out to be the cam phasers even though it sounded like it was coming from the lower end.
03-10-2016, 02:32 PM
Hot Idle lower end knock?
