light tapping on start up 03 Durango.4.7 51,000 mi

Changed all lifters! motor purs after it's warm. Only
clicking left is the injectors (normal continuous soft
tick). Still have start up tap which desipates after a
minute or so. Guess you just have to live with it. Dodge
mechanic says piston slap. I think it take time to get oil
to the functing mechanical parts where oil is needed.  
Tensioners, lifters, and others. Oil is important, too
thick of oils will gum up and not transport through
ports well, too thin of oil will not protect as well and
may break down quickly. Temperature is a factor! If
you like your car use synthetics. I us the typical 5w-30
mobile one - one qt for the lucus stabilizer. In cold do
not use stabilizer.
If you live in hotter climate jump to a 40. The noise I
live with is because I bought a Mopar product.
Mechanical noise happens to all engines. Understand
oil protection and mechanical knowledge is the only
safe guard. PS still drives me crazy, do I walk away
from Durango until it warm....try it