Starting a couple months ago I noticed a delay in oil pressure at start up with my '98 Ram 2500 12v. It takes about 4 seconds after start up before the oil pressure needle moves up from zero. Additionally this past Friday, for the first time, I heard the warning tone and noticed it dip momentarily when I stopped and put it into park. I took it by the diesel shop I use and they said to not worry about it unless it loses oil pressure while I'm driving it.

Any thoughts? Am I worried?

Thanks!