Hello to everyone here..I'm new to site and have some questions about the problem I'm having with my 2011 Ram Bighorn..5.7 liter with MDS.. I bought it used 3 mnths ago and of course the warranty is up and I'm having a misfire in cylinder number 3..I've changed the plugs/coil pack/injector...no broken rocker arms/valve springs...etc... I did compression test and have a little over 150lbs in 4 of the cylinders I have checked..I checked 1 and 3 and 2 and 4 cylinders...I was told that having the wrong weight oil can cause a misfire..that it messes with the sensors or something to that effect..so I'm changing oil tomorrow mornin... now at an idle it's a little rough...and even going really easy up the,rd it's ok somewhat. But soon as I step on it a little harder to pass someone or get on highway the check engine light symbol that stays on all the time starts flashing and the truck starts running really rough and I lose power and pull over and shut it off right away..so it only happens when under a load...I'm at my wits end with this damn truck.. anyone have any other info that may help me? I really appreciate any help..thnx much