I had my check engine light come on the other day in my 2104 Ram 5.7 with about 60,000 miles on it. I have not have any codes come up before except the gas cap loose or small evap leak and I changed the gas cap at that time with no more issues.. I checked it with my code reader and codes P0300 and P0219B came up. I was worried that maybe the camshaft issues that other 5.7`s were having may show it`s ugly head and that may be my issue so I took it to the dealer. They brought the truck in to get it checked out. They asked if I had changed the spark plugs recently and that the spark plug that they pulled from #6 cyl looked new. I said no because my truck uses iridium plugs and they get changed at 100,000. They said one of the #6 sparks plugs was loose. The spark plug and plug hole had good threads and they torqued up fine according to them..

Now my question is what would cause one spark plug to come loose after 60,000 miles? Is it a common problem that I am not aware of or it is something else going on?

Luck of the draw.The plug didn't get tightened enough at the factory.

If the code was cleared and truck has not thrown code again, and the truck is driving as normal, dont lose sleep over it. From what I've seen, you should probably run 2 or 3 tanks of concentrated cat safe fuel cleaner through it as a preventative measure as this code many time pops up in relation to clogged injectors.

Running fine now and the codes were cleared. I will add some fuel injection cleaner. BTW, The code the dealer gave me was P0306.

It is odd that your original code was P0300 and then the dealer says P0306

With two spark plugs per cylinder making noticeable ignition missfire less likely than single plug cylinders,
I tend to agree with the above comment that a clogged fuel injector
would more likely trigger the original codes you read of P0300 and the Bank2 air fuel P0219B

My experience with OEM Chrysler Champion plugs loosing their welded on platinum alloy discs makes me suspect too,
but yours appear to be NGK laser welded which should be a quality piece.

Not sure about that. The codes I had were on my home scanner. Maybe some older codes??? I am not schooled very well on using the scanner. The dealer only referred to the 306 code and said nothing about the others. I will dump some Techron in the gas just in case. My truck sat there all day and they brought it in near the end of the day. They seemed to be in a hurry due to the holiday and were just trying to get the cars in and out was my impression.

The 306 is def a #6 cyl misfire, but there are so many variables applied to these misfire codes. I'm glad it wasn't a cam/lifters issue.

You got that right. I was happy about that too!