I saw a video by Lake Speed Jr talking about additives in oils. He seemed to indicate that calcium levels over 1500ppm were not good for DI engines. My 14 MB E350 is DI and spent it's 72k life on Mobil 1 0w40 or dealer 5-40 oils. The 0-40 shows 3pk ppm of calcium while the Quaker State Euro 5w40 shows 1500ppm. Would it be wise to switch to the Quaker State 5w40 229.5 oil for the future? Engine runs fine at present. I've been using Quaker State 5w40 in my other MB 3.5 DI.