Hello, Is there some reason that BMW (European Engines) use a thicker oil than North American Engines?
I have a 1991 BMW 735iL with 90,000 KM on it; this car has never seen a winter. The owners manual suggested to use 15W40 for the temperatures -5F to 90F and 20W50 for 15F to 120F) I have been using Castrol RX Super 15W40 until I lost my source for it. This is a diesel oil API rated CH-4, CG-4, CF-4 CF/SJ. I don't know what these ratings mean, but it does say that the oil can be used in gas or diesel engines. I do not want to be bothered with synthetic oil due to the cost, and the fact that this car is only used about 10,000 KM per year in the summer only. I only change the only once per year.
Any suggestions?
I have a 1991 BMW 735iL with 90,000 KM on it; this car has never seen a winter. The owners manual suggested to use 15W40 for the temperatures -5F to 90F and 20W50 for 15F to 120F) I have been using Castrol RX Super 15W40 until I lost my source for it. This is a diesel oil API rated CH-4, CG-4, CF-4 CF/SJ. I don't know what these ratings mean, but it does say that the oil can be used in gas or diesel engines. I do not want to be bothered with synthetic oil due to the cost, and the fact that this car is only used about 10,000 KM per year in the summer only. I only change the only once per year.
Any suggestions?
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