Hi there all, new to all this. I have a 2006 YD2.5 d40, it’s done 290,000kms but after a few modes is still running good, apart from a bit of blow by and an eye watering exhaust smell, I have changed the turbo as it failed due to the mechanic putting the oil feed line to turbo gasket in backwards so wasn’t draining back to sump. I’ve also just put on a 3” with muffler pipe and snorkel, it doesn’t loose water and no oil leaks. I am going to put a catch can on as doesn’t have one and oil going into hot pipe so after cleaning pipes and intercooler don’t want to do it again, I am using 10w40 nulon full synthetic oil ( should I go thicker?) or is there an additive I can use? Pictures to come . Thanks in advance for any help.