I'm not too worried about it. It's definitely not as loud as the one I heard when another member was worried and posted a video..I did just go out to the truck after posting, was checking bolts, (no spark plugs or others were loose), but I saw a little oil residue by the fill cap. I was looking for maybe exhaust manifold signs of leakage. I thought initially maybe there was some spillage when the oil was changed, but being as meticulous as I am, I knew I wouldn't have left it like that. After checking the fill cap, and concluding that it wasn't exhaust soot, I went bolt checking. I wasn't sure what size the valve cover bolts were, so I was trying different ones, none would fit, each were loose fitting, THEN I noticed that the bolt I was trying them on was just THAT loose, I don't know how it happened, or when, but I went ahead and snugged it back up, and checked the others. This, I'm sure has nothing to do with the noise, because with the engine running, I put my calibrated ear up to the motor on each side of the valve train and injector areas, and it was equal on both sides, but I thought I'd tell a story! Can I get in trouble on here for writing a Mini Novel?!