bwFX42006

I've noticed mine does it intermittently as well. I'll have it checked again at another dealership, just so I have substantial proof that I investigated the issue. That way, if something does happen in the future, I'll have proof I at least made an attempt to resolve the problem.

It's never given me any performance issues, it's just an odd noise.

Heel70

Try changing over to full synthetic 5w30 if you haven't allready done so at the next oil change....I bet the slight knock will not be as bad. Same issue with my 2012 5.0 from a while back, wasn't using any oil, no performance issues just a little knock at warm idle. Switched to 5w30 and noise is substantially quieter if not gone.

msgross

anyone try Lucas oil stabilizer in lieu of a quart of oil?

bwFX42006

Did you use motorcraft 5w30?

SOMDguy1986

My 2012 is currently knocking hard at idle but there is no oil loss so i am going to try this. Thanks for the tip

bwFX42006

Used Royal Purple 5w-30 and a new Motorcraft FL-500S filter over the weekend and seems to idle a bit quieter now. You can still hear a slight knock, but it's a lot better than it was before.

BUILTTOLAST

Not that I think using 5w-30 is a huge deal or bad thing,but it's not going to cure/fix your problem,it's an attempt to put a band aid on the problem.
Ford calls for 5w-20 in the 5.0 and there's hundreds of thousands of 5.0s running the recommended 5w-20 running perfectly fine.
My advice,dump the truck/trade it before it gets worse.
Not worth losing sleep over.
That's just my opinion.

bwFX42006

I have an extended warranty through ford premium care for another 20,000 miles so i'm covered if anything happens.

As for the oil, just wanted to give it a try. Can't hurt anything. I'll probably trade in on a new powerstroke F-150, if they ever come out in 2018 like the rumors say.

BUILTTOLAST

Well if you have an extended warranty and plan on dumping the truck by 2018 than sure.
Just make sure you don't let Ford know that you used 5w-30 oil as they will use that as ammunition against you if the motor needs to be replaced by then.
Good luck with the truck.

brihvac

If it was an oblonged cylinder; then why would it not make the noise since day one?