There has been much talk recently about the benefit's of this grade of oil. I think the best value is in the high tbn's and the ability to run some what extended drain intervals while paying around six bucks a gallon at your local walmart. Also the ability to keep a engine very clean. But here is the question- If a thicker oil can cause increased friction which leads to more heat how can this grade of oil still maintain very clean engines? I thought that more heat might mean more varnish and deposits. It seems that the only drawback to this grade is the hard pumping that could happen at very cold temperatures, if a person is using the non synthetic type. We continue to see great results from this grade and I also wonder why more major car makers do not want it in our vehicles? My favorite is the penz. LL 15-40. What do all you experts think? Thanks, Ryan