I have a Honda Ridgeline that usually goes around 7,000 - 7,500 miles going by the olm. I was peeking down the fill cap with a flash light. I noticed some sludge starting to biuld up on top of the bolts that hold the rockers down, didnt see any more other than that. It only has 60,000 miles on it. Could this be from running dino for those long oci's, or could it be from running supertech dino all its life? Should I go with a synthetic or switch to a better quality dino?