If your car/truck is powered by a Nissan/Infiniti VQ35 (probably same for a VQ40 engine too), you MUST NOT LEAVE THE DIPSTICK OUT WHEN FILLING WITH OIL!
The VQ is a very nice engine, overall, but its designers really forked up this part of the design. The dipstick has no guiding tube -- you must reach the floppy stick down into the dark and thread it into a little hole on the side of the block. That little hole, which could have been put darned near anywhere, was placed directly below the oil filler opening, which of course, is up on the cam/valve cover.
When you add oil with the stick out, it proceeds to spew out of the little hole, making an awful mess.
Could it be worse??? Yes, of course - most of the spilled oil ends up on, you guessed it -- the exhaust!