scotch
+1y
If you're going to invest the time to take them out, then I would probably replace them as long as you're "in there." Even if you end up selling the truck, you'll probably get a better price with a nice quiet engine than with it ticking away. Somebody who knows and understands hydraulic lifter noise might not be bothered by the tick, but most people would probably be spooked by it.
But if cleaning doesn't do the trick, and you don't mind going back in a second time to replace them, then give cleaning a try.
Here is a little video of the process:
Lifter cleaning..... " target="_blank" target="_blank
While you're in there: PCV Grommet (this a 2.0/2.2 - but the same applies).... " target="_blank" target="_blank
And a few other tips while you have the valve cover off: " target="_blank? target="_blank