I've been living with this annoying rattling or ticking noise for a while. I finally tore into the top end and am going to replace all lifters, rods, and arms as well as timing chain. I'm hoping this will solve it. But since I am this far into the engine, I am thinking of pulling it and looking at the bottom end. I guess my question is what you guys think the sound is? Is it wrist pin, piston slap, bearings, or just my lifters. I'd have to buy a engine lift and stand if I go all the way with it, but also don't want to completely rebuild the engine just fix what's making noise.

 

Details help.
Your public says 2000 B4000 w/3.0l engine. Correct?
How many miles? Overall condition?

Make another short vid from the engine bay...door closed...no warning beep.
What I heard sounded more light-weight...

 

It's the 4.0 OHV. I have a better video here.

 

The file doesn't open.
Why is it different than the one which worked?

 

I had to edit it in Clipchamp because the file size was too big. Let me see what I can do

 

If it was warmer, you could try a brief load of 15W-40.
It'd be cheap as it could be for an experiment.
You'd not waste oil; you could always trickle it into vehicle and OPE top-ups.