I also think it is probably your plenum gasket. Burning oil in you air/gas mixture causes carbon to build-up in the cylinder wich in turn raises your compression ratio and leans the mixture out. So, wait until you get it fixed to waist a bunch of money on fuel system cleaner.
Here s a page w/ the possible causes of ping and how to get rid of it:

http://www.dodgeram.org/tech/gas/Trouble/ping.htm

The little bs test that the manufacturer came up with to test the plenum gasket is just that...bs. Mine passed that test with flying colors, but I still had oil sitting in my intake. The problem is that the intake is aluminum and the belly pan is stamped steel. As the motor heats up and cools down the metals expand and contract at different rates, rendering that chickensht paper gasket they put in there useless. Make sure when you fix it (DO NOT LET THE DEALERSHIP DO IT) use an aluminum belly pan, felpro gasket, and rtv sealant. If you really want to burn air/gas instead of air/gas/oil, put a filter in the vacuum line goin to your pcv valve. Sorry if sounds like I'm ranting, but I just put new heads on this past weekend and it took me three hours to de-carbon the cylinders and piston heads. BTW this was after spending ~$50.00 on Techron since I replaced mine. That stuff may clean your lines and injectors, but it don't do squat for your combustion chamber.

 

this is going to be a bigger headache than i was anticipating

mopowar - what part of richmond are you in, im in glen allen

 

Southside. Are you familiar with the pony pasture? If so I can throw a rock and hit the parking lot. PM me a number. Maybe I can help you out.

 

i heard about running a little bit of CLEAN watter down your intake to clean out that carbon... not sure if it works well.maybe someone can back me on this..very simlar to water injection to cool the intake charge temp...but i geuss what happnes is if you ahve enough water in there it turns into steam when blown up with the combustion and really cleans the hell out of your cylenders and walls

 

do you change your oil regularly? the first step to taking care of a truck and keeping problems from popping up is to make sure you are changing its fluids at the proper time and not just changing them every now and then. basically just make sure that your problem isnt your own irresponsibility.

 

You can change every fluid that your truck holds every 10 miles, but, if your intake manifold is sucking oil out of your lifter gallery, your motor is going to run like ****e, and ping like hell. I think that most of the people here care enough for there trucks to perform regular maintenance on them. I mean if they were just on the internet killing time they'd probably be off on some **** site.

shott- I've heard of that too- pouring boiled water down there. I've also heard rice. Maybe mixed vegetables would work. I've never actually seen anybody do it and would be to scared to try it. You imagine- your neighbor walks over-"what you doing" you say "rebuilding my engine" he says what happened..... "well I had this rice"

I know that, with the heads off, it took a whole lot of carb cleaner and even more elbow grease to get the piston tops shining like brand new.

 

lol..i heard some beef broth and Petes Red Hot mixed 50/50 .. takes about 40 gallons poured directly into your intake... makes it run like a race car!!! lol... i just heard that after testing cars and trucks with water injection during teardowns to inspect the cylinders they were spotless almost like brand new..after 100,000 miles... it was in an article some where.. cant remember... peeked my attention but ill never pour water down my intake..hell im worried about water getting sucked into my CAI during rainy days... there i go jackin threads again

its been proven that a good water injection system reduces pinging completley... and a side affect of it is that the water turns to steam and cleans the hell out of the comustion chamber...eventually reducing carbon build up and then obviously lowering the compression ratio .. no more ping