440 Oil Weight

Just as important is the type and brand of oil filter, also included in the Ram forum oil discussion. There are certain brands of filters to avoid, and certain brands within brands to avoid. My own preference in filter is Wix 51515, and 51515XP. But there are others equal to or maybe 'better', but cost is a factor for me, also. For oil, I've used Quaker State ($13.97/5qts @ WalMart), or Castro GTX. Some people are really into synthetic oil, but they are more expensive. Some people are into what I call "designer" oils, like RedLine, which I have heard a lot of really favorable reviews, but they are very expensive and somewhat hard to get.