I have a 2000 Blast with 7600mi it leaks oil from the top front of the motor. Changed the valve cover gasket and it's not the problem. It leaks quite a bit but only when I'm at higher RPMs like on the freeway I will end up with oil covering my right leg. I have looked around and I guess it's the "rocker box" Has anyone experienced this and knows the solution and weather it's a fix I can do myself. Also it has began to start "ticking" it never started ticking until I put 20w50 oil in it which is recommended for my climate (Las Vegas) so I'm going to take the oil out and put in a different weight. What would be a good weight since what the book says appears to be wrong.