2003 Explorer 4.0 engine noise under load

[Cubanlorenzo]

Have a 2003 explorer 4.0, and between 2500-3000 rpms under half throttle load, i have a noise coming from my engine.sounds like a loose heat shield rattle but it is not. As soon as i pass 3000 rpm's the noise goes away until the next gear between 2500-3000. Happens all of the time. Cold,warm. Wet, dry. Sorry for being vaige but this is what i have to go on any suggestions?

Timing chain?

 

[Maginley]

i have a 99 4.0 was hearing some similar noises but mostly at idle. i knew my timing chain was shot i actually ending up dropping a good amount of cash and got a brand new engine with updated specs and more durable design of critical parts such as the infamous weak timing chain system. its been 1000 miles with the new engine and im still hearing the sound. i have a few ideas like maybe egr valve or vacuum valves. i really wanna fix this because its alittle annoying and its starting to worry me. have you tried replacing anything yet?

 

[KPPCExplorer]

Sounds like timing chain. Mine has been doing this for years and hasn't blown up yet, just really bothers me every time I hear it.

 

[da2962]

Sounds like the issue I have just gone through (also an 03 4.0). At first I thought the same thing, and went from stem to stern looking for something loose that might account for the rattle and found nothing. At idle it was relatively quiet, and once I got up to speed without giving it any more gas than needed to maintain speed it would quiet back down, but once revs went up there it was. Long story short, was timing chain tensioners in front. Waiting for the call from the mechanic now to pick it up and find out the final cost.