- Nov 9, 2009
- Western Australia
hi guys i have done a search and nothing answered my question. i would like to know what is the best oil for a 12ht. i have been using penrite 15w50 which is a semi synthetic and it has been running fine on that, however i have been talking to a few people and they are saying that a full mineral oil is best for older diesel engines so i am thinking of changing to penrite 20w60 which i a mineral oil.what would you guys recommend, she has done 500,000km and apparently was rebuilt at 400,000km.