Is This Piston Slap

Here is my senerio.

Start the truck (05 Ram Hemi 4X4 QC) from cold and runs smooth and quiet, Then after idleing and warming up for around 4 min. starts a lite metalic thud knock sound and will stay that way till driven then gone but the truck always has a quiet diesel motor sound to it.

But this knock sound has become louder since the first oil change a few days ago. to me it sounds just like a piston hitting it there.

I took it into the dealership and they heard it to and documented it but then kept it overnight and heard it again but said it couldnt be diagnoised and they couldnt figure out where it was comming from. Needless to say its going in to another dealership this week but has anyone else had a kind of knocking after idleing for awile. and is piston slap a real problem? I know some people with chevys that have it and now have over 150,000 miles on them. sounds like crap but still runs good.

don't take it to a dodge dealer. find a simi truck shop in your area. most people I talk to said the reason they bring there trucks to us is beacuse the dodge dealers have no clue about anything on the diesels

It's not a diesel.

BleedDodge, I sent you an email asking the same thing i did here? You seem to be quite Mopar educated I was wondering if you have any opinion besides the "just drive it" i got from the oil change guy at dodge.
Thanx

Didn't I tell you that earlier too? Haha.

Seriously though, when you had the oil changed, did you do it yourself or did you hire someone to do it for you? Did they remember to put the right amount of oil in, if they did at all? You never know.

Going by what I know, the motor is far from being broken in, it's pretty much brand new, and I'm pretty sure you should just relax and drive it. If oil pressure or power starts being lost then I would believe there is a reason to be concerned.