Castrol is the only oil I use even when I could get my oil for free from Valvoline. They used to be a small independent company that bowed to nobody, of course they ended up being bought out but the formula remains the same. No paraffin wax based oil from them. If I'm not mistaken Penzoil did go away from a paraffin base but I wonder how they did this since their reserves are still from the same wells.
