I've been using Liqui Moly Long Life for past 50k miles in my 2005 Mercedes E320 CDI and I recently came across Shell Rotella T6 in the diesel section of Wal-Mart. It has the MB 228.31 certification spec on it. I'm not sure if I can use it in my car. I don't want to start an oil war, but the price is way cheaper and it's way more readily available. 1. What MB spec oil did Mercedes specify for my Benz back in 2005? Currently Mercedes diesels use 229.51 2. Would a MB 228.31 spec oil work in my Benz?