Originally Posted by eng

It should be fine. The 10 compared to 5 for sure is alright (even says something to that effect in most Nissan FSMs). Usually 5W oil is used when you're going to see sub-zero F temperatures. The 20 and 30 weight is were any problems would show up, since the 30 will be a little thicker. However, it's also quite hot recently so the fact that it's thicker will be offset some. That and oil thins out as it's used. If you were going to see any problems it would have been right after you put the oil in. I'd just keep going with the current oil and change on schedule.