Hey everyone, been awhile since I posted here, been lurking for awhile. Anyway, this is going to be a tad long, so I'll get right to it.

As a few of you may know, I own a 2011 F-150 FX4 Supercab 5.0L V8 that I purchased new in June of 2011. Anyway, The truck is currently at about 45,700 miles. It's been very well maintained, I've never been late on an oil change and up until my previous oil change I used motocraft 50/50 synthetic blend oil, my last oil change I bumped up to Mobil Full Synthetic. In all of this trucks near 46K miles it's only towed about 120 of those. And I rarely ever romp on it. It's usually a cold day in hell if my tachometer ever goes above 3000RPM. And the only thing that's currently been altered on my truck is a Flowmaster Super 10 Muffler and Resonator delete duel exhaust set up. Other than that, it's bone stock.

With that little bit of background knowledge, that brings me to why I am here. I've noticed that when warmed up to operating temperature my truck seems to make a very VERY slight knock when idling. The sound is so slight, that it really can't be heard inside the cab, and when I give the truck throttle (weather in park or accelerating in gear) there is no out of the ordinary sound what so ever. The engine seems whisper smooth from inside and in day to day driving. It's just that little oddball sound heard at warm idle that's throwing me off.

I've been lurking on this forum and a few others lately and I've worked myself into great paranoia fearing that my truck could suffer from the oblong cylinder boring issue that plagued some of the early 5.0L's. I know this sounds stupid, but I honestly cannot remember if the engine always made that noise or not. It did seem as though the engine made a little more noise after I switched to Full Synthetic Oil, which was around the time I started noticing this. I don't know if the switch to oil types would make any difference or not.

I want to iterate that it is such a faint sound, I've never had any friends or family comment on it when riding with me. I almost want to say it would be completely un noticeable to anyone but myself. But because I notice it, and because there is a known issue for knocking with early 5.0L's Its got me on edge.

My truck is now out of Warranty, and has been so for about 10,000 miles. This is what scares me most. I've heard that the only fix for the cylinder boring issue is a replacement block which costs anywhere between 8,000 to 11,000 dollars. My question ultimately to you guys, is this. Does your 5.0L have any weird characteristics that sound familiar to this. I'm going to try and post a video of mine idling, but in the mean time I'm going to leave this video here for you guys as this is closest one I could find to the noise my truck is making.

(This Video is not my truck but this is very close to the sound)

 

Good gosh I recognize that noise well. Dont panic now though, there are other things that caused this noise on the early Coyotes. The water pump being one that I can think of off the top of my head. Unfortunately my 2012 was one of the ones that needed a new power plant, and the noise was evasive as evident in that video. I now own a 2014 with the same engine, no noises at all like my previous 2012. Good luck with your findings, I hope its not what is associated with that noise.

 

My 2011 5.0 has similar noise, it comes and goes. Injectors?

 

Id have the oil tested by a lab............................

 

The injectors sound like a sewing machine. They are loud, but this noise is clearly not injectors. The injector noise is present in my 2014 5.0, but not the knocking tick noise.

This is an excellent suggestion, and I am ashamed that I havent even thought of it when I was trying to chase that noise down with my truck. Excessive wear metals on the oil analysis would be probably the cheapest way to find out if you need to start saving or looking at another noisy component.

 

some 5.0 have had issues with, I believe, the number 7 cylinder warping and causing that same kind of knocking sound.

 

Has our oil pressure lowered any
Could almost be a bearing. Like Brokenleg mentioned earlier, get the oil tested.

 

My 12' 5.0 does the exact same thing. Spent 67.00 taking it to Ford and having them tell me there was no abnormal noises and all engine codes checked out fine. I stewed about it for a month, mine also uses more oil than I would like it to. What happens is gonna happen, what the heck just drive it . Ps it might need to be opened up once in awhile if you baby it all the time, the 5.0 was made to run...

 

Having the oil tested is an excellent idea & u can learn a lot from it
I have used Blackstone for years now, reasonable & will talk to on the phone if needed, to explain your analysis report in simple terms...lol

The not babying it all the time is a good suggestion, even though a lot of people cant understand that. Years ago I worked in a GM dealership (which is why I own Fords...lol) & honestly a lot of complaints or emission issues were corrected by running the **it out of it for a few minutes, then clearing codes. It's a very long explanation as to why constant babying causes issues & I don't feel like typing all day. I am not saying rag on your truck, just don't drive it like a Prius, that your trying to hyper-mile.

Breakdown....Order a oil sample kit from Blackstone (free) & next time u change the oil, send it in.
Also don't drive it like a Prius, but u don't need to be bouncing off the rev limiter either.

Good luck

 

Im in the same boat.10,000 miles past the 60,000 mile power train warranty.Ford told me mine doesn't rattle enough to warrant a repair.A motor with 70,000 miles shouldn't rattle.So my guess is Ford will tell you to go away.They did me.

 

Hey 460 CI
You said you've got 46,000 miles and are out of warranty.
Isn't the powertrain warranty 60,000 miles?

Edit: Never mind. The warranty is also just 5 years. And
you're past that.

 

How do we upload videos to this site? Does it have to be through an external source like Youtube?

 

Yes. At least that's the only way I know that it can be done. Even as a paid supporter.