4.0l v6 knock in bottom end
Sounds like there is a problem, I’d get that looked at.
First things first, I assume you checked the oil level, and there is enough oil on the dipstick? If the knock has only been present for a short time, less than 60 miles, I would attempt to replace the bearings, etc. from below. Given that this is a truck, it already has pretty decent ground clearance, and if you jack up each corner and place a spare steel wheel under each tire, you will have plenty of room to lay underneath and do this procedure.