02 durango slt plus knocking noise

I purchased a used 2002 Durango SLT Plus in June of this year. 77,000. miles. About a month ago I notice when I start it on cool days there is a knocking-- like a lifter. Once it runs about 3 or 4 minutes it goes away. Took it to a mechanic and they put some oil treatment in it. Colder weather it is louder. Anyone with this problem ? and if so --What can be done? I love this SUV otherwise.

it sounds like it could be a lifter.after driving & noise goes away & turning
engine off(after sits awhile) does it start tapping when restarted or is it a 1 time thing that accurs on first start up ?besides replacing lifters
you could just start using an additive with each oil change.

If it sits for a few hours or overnight it makes the noise. Seems to do it when the engine is cold. I usually let it run for 3-4 minutes to make sure the knocking goes away before I drive it. Thanks for any help or ideas. I have added an oil additive 2 times. Hope it isn't something to costly.

costly to replace lifters.but if its only on first start up then i would'nt
worry about replacing them.