I usually won't start hearing this sound until the motor has warmed up. It's changed in rhythm since last week.. and I wanna say for a day or two it was fairly quiet. Now it's sounding pretty loud. For a while it was a taptap, pause.... taptap, pause... it changes.
Just replaced exhaust manifold gaskets. All connections throughout exhaust are tight. I can hear the sound when I put a stethoscope up against exhaust pipe. Seems loudest directly on cylinder head, however doesn't seem louder when I open oil fill cap?
I just replaced the timing chain tensioners as well, the screw in hydraulic ones. I never heard the death rattle, except for a couple times when I was on an incline and it would go away, and it wasn't that loud. More so preventative. Haven't heard any rattling since the new tensioners.

I really am frustrated at this point. I haven't taken off the valve covers yet, as I understand it can be lifters. I will probably be trying marvel mystery oil soon in case it's a stuck lifter. I've never replaced a lifter before. Truck is a 2005 Ranger 4x4 with 4.0 SOHC and 5r55e.
I have the entire service history of the truck and it's gotten regular oil changes. Only 120,000 miles. I bought it from a county mosquito exterminator. 5r55e blew on me 2 weeks after I bought it, I believe because someone had the vent hose plugged. I got a reman 5r55e, now dealing with this. Thanks in advance for any help!

 

To me, does NOT sound like V6~4.0L~SOHC broken TimingGuide "DeathRattle"; something else?

 

Think it's a cam follower / lifter type thing?

 

Based on your description, it seems like it's dependent on the engine's firing order. Did you check to make sure the exhaust manifold wasn't warped? What was your reasoning for replacing the manifold gaskets?

 

Not exhaust related and not timing chain related, to irregular

Could be hydraulic lifter issue, which can be irregular, does the noise go away at a slightly higher RPM, i.e. higher oil pressure?
After oil is warm its thinner of course, which fits as well

If that's what it is it won't hurt the engine to run it this way, and it should become a more steady "tick, tick, tick" over time

 

Yes, it seems to go away at higher RPM but it's hard to tell, because most of the time it's not that loud. I just put in a half quart of Marvel Mystery Oil to maybe clean up the lifters. Just did spark plug wires in case they were arcing each other, but that didn't make a difference. Thanks for your contribution! Hopefully MMO helps.

 

I replaced the manifold gaskets as an attempt to throw parts at it basically, and because the sound was coming from that general area. I did check if they were warped by putting a square up against both of them, and they were both perfect. Thank you for your contribution to the post!!! I am trying Marvel Mystery Oil in case it's a dirty lifter.

 

This video was the loudest the noise has ever been. It's usually quieter than this, which was a great time to grab a video. I really am in love with the truck, got some wheels for it, wanted to do it up nice and was hoping it would last me up to 300k if I maintain it well, even investing in a reman tranny after my luck. This noise has really taken away the enjoyment of owning the truck, as I'm worried it's some potentially catastrophic internal problem causing me the need for a new motor. All I can think about with the truck. Already investing 2200 in the tranny and spending 3 days fixing it, the noise is just the icing on the cake. The noise started maybe a couple days after I bought the truck, but it was probably there the whole time and I didn't notice it. I've probably owned it 3 months now. I will be reporting back to the thread with my findings for any future onlookers.