2004 150 5.4L 2wd supercab short bed with 180K on the engine. Its been making engine noise for the last 3 years or so, slowly getting louder, sounds like a diesel truck sometimes. I assumed it was the phasers going out, it has loud days and quiet days though. So I've been telling myself to get around to ordering parts for the phaser swap and get it done.

Yesterday I did my regular oil change, MC oil filter and 7 qts Castrol full synthetic 5w-20 oil. After I was done I started it up as I always do to check for leaks. As I moved from above the engine to crawling underneath I noticed the noise was significantly louder under the truck. I started rethinking the phaser diagnosis of mine. The top side was actually pretty quiet, normal injector ticking and what not. So now I'm wondering if its a possible knock in the bottom end. How could I verify this? I was thinking drain the oil and drop the oil pan, but would I be able to see much? I need to get a stethoscope and see if I can narrow it down to a certain area but how else can you diagnose a rod knock? Truck runs just fine, actually quite good for its age, good mileage and power, no stumbling or out of the ordinary symptoms.

 

A rod knocking would lead to failure quickly. This would indicate something else is making the noise.

 

The best way to determine a rod knock is to take the pan off the bottom and wriggle the end caps to check for play. Its more intrusive but its probably the only 100% sure way to find out for sure.

Typically: (I have seen exeptions)

• Rod knock does not vanish as the engine warms.
• Sound is consistent but varies only with engine rpm (exeptions.. I had a vortec 5300 that would vanish under load)
• Rod knock can sometimes sound like piston slap or a bad wrist pin.

 

Would I be able to check the wrist pins from the bottom too? Also would the oil pan gasket require replacement when I drop the pan? The noise doesn't go away as the engine warms up, in fact that's when I hear it the most.

 

You probably won't be able to check the wrist pins very well from below. Sometimes you can depending on what position the crank is in.

​​​​​​I'd recommend getting another gasket for the oil pan and replacing it just in case. You're not going to do anything more damage then what has been done already. If you find the rod with the knock, id take the cap off and inspect the bearing anyway. You could try to replace it but it's been my experience that rod knocks are seldom repairable without rebuilding the engine.

If you get under there and there is no play then I'd try to see if there is any play in the wrist pins by trying to shake the rod itself. That's not going to die you much but if it's open you might as well check. Check the oil sump and pan magnet. Look for excess material or brass. I'm not sure what Ford makes the bearing out of.

Sometimes the valve rain can cause some odd noises. If your problem isn't down below, pop the covers and have a look there.