[Viva Las Vegas JDR]

I am what you might call a gauge watcher. I am always looking at the gauges to make sure all is well. I noticed the oil pressure dropped considerably. I drove a few miles and no change. Just when I was going to pull over the pressure when back up to normal. Why did the pressure drop ? the oil has been changed with less than 500 miles on new oil. I thought of the oil pump going out but that's just a guess.Any kind of help would be grateful.