Being new to the 4.6, I'm wondering if this diesel sound is normal?

[geosnooker2000]

Sounds like rockers knocking or a diesel engine. Truck is new to me (3 weeks) 120k miles on it, and seems strong and gets good gas mileage (21mpg if I hold my tongue just right) . Does not run hot. Oil level seems correct. It is very faint, but it's definitely there. Am I worrying for nothing? Or is this a known issue that will turn into something?

 

[Explorer_PL]

Read about camshaft phasers on 3v engines

 

[geosnooker2000]

Just checked out a couple videos on YouTube. Very interesting... Thanks! Any risk in letting it go 'til the summer?

 

[Christobal65]

If you can't replace them now and can deal with a check engine light just unplug both phasers it should help reduce the issue with less risk of a catastrophic failure

 

[thebrakeman]

If the noise goes away after 1-2 minutes of warm-up, it's 1 or more broken exhaust manifold studs.
If noise continues after 1-2 minutes of warm up, see other recommendations.

 

[geosnooker2000]

If you can't replace them now and can deal with a check engine light just unplug both phasers it should help reduce the issue with less risk of a catastrophic failure

I'm not getting a CEL. Like I said, it is very faint. Most people wouldn't even notice it, but coming from the 5.0L, this engine sounds different. It *MAY* just sound this way. IDK.

And @ thebreakman -

This is definitely after warm up. If I had to guess, I would say this must be the very beginning of the phaser problem. When it's not bad enough to throw a code yet. But again... I'm guessing.

 

[Christobal65]

The 5.4 and 4.6 engines have a very different sound (not referring to exhaust note) than the older 302/5.0

 

[michael loibl]

Christobal65 is saying you can disconnect the phasers, but then u will get a check engine light. This may help til you can resolve the issue. I did it on a 2006 expedition 5.4 successfully