I have recently bought a 1992 Mercedes w124 200D with the om601 engine. The car is in very good condition and I plan on keeping it as a classic. It has 145k miles on it. The car is going to be used only for two weeks on Christmas holidays, two weeks on Easter holidays and 2-3 months in the summer. That is about 3k-4k miles a year. I drive it mostly short distances of about 10-15 miles, but sometimes I take it for a 100mile round trip on highway. it has an 4 speed automatic gearbox that keeps the revs very high on the motorway. At 70mph it turns at about 3600rpm. I would like your advice for the best oil to use in this engine. It currently has in it 15W40 HDEO. I was planning to change it to Mobil Super 2000 10W40 for the winter season because the hydraulics have been making some noise and thought that a semi synthetic might help with that. Is it a good choice? Should I stay with an HDEO for this engine or a regular PCMO is fine?
Thank you
Thank you