I have a 1990 runner with a v6. It is 4 wheel drive. Friday I changed oil in it. Nothing looked out of the ordianry. Drove It a little this weekend and everything seemed fine. Driving to work today and it started knocking horrible. I thought maybe I forgot to out the plug back in or something. I thecked the oil and it was full. Driving it I noticed that the thing barely has any oil pressure. I put 5w30 oil in it. Has anyone else ever have this problem.