Well i been searching through the forums but didnt really find an answer. I am doing an oil change and wanted to clean it all out. so is there a good cleaner product that you run through the engine before you put new oil in. Also my car did not come with manual when i bought it so does it take four quarts and i seen on other threads 5w 30 i have a 97 gtp. And is there and good oil additives for helping with a little knock and gaskets?