My 318i has about 78K on it. My mechanic did a full check on the engine, and found it to be very clean. As a result, he suggested that I start using a synthetic oil, 20W50, because of the high temps here in northern Alabama.
Here's my question...I have reseasrched the issue, and AMSOIL is very highly rated by what appear to be independent tests. My mechanic has had limited experience with AMSOIL, but says that his experiences have been that AMSOIL works well in new cars, but not so well in cars with mileage where mine is.
What recommendations would you have for oil choices? He recommended Mobil 1 SuperSyn, but they don't carry a 20W50 grade. Help is appreciated...