[Cait Sith Cat]

So I was a moron and drove through some wicked water and got water in my oil and intake. I drained the oil out (it looked white) and put some fresh oil in, which I will probably change a day or two after I get the truck fixed (just to be sure I get all the water out).

My truck starts up fine now, but there's a terrible knocking sound that varies with the RPM of the truck. A friend suggested it might be a loose rocker arm, but I don't know how that would corelate with the water I got into less than a week ago.

What could this be? Is it the rocker arm? How can I find out what it is and fix it?