Generally this sound is the valve lifters. The injectors are really, really quiet, just the slightest little clicking sound. Not something you can hear from inside the car. How often are you changing your oil and what type are you using? These factors can effect lifter noise.
the dealership is wrong , your not getting oil to the top of the motor, this engine has this problem on every 3.5 according to a friend of mine and he is the service manager at a large dealership in Az. , The pin shafts need replacing and should be under warranty with dodge this is part of the power train and 100, 000 miles is the coverage that Dodge is liable for . On your next oil change add 1qt. of lucas motor lube and this will quiet it down some what, it is loudest in the morning.