Is it or is it not true that BMW started selling synthetic oil in their engines only a few years ago? I do not know for sure myself, but did 99's even come with synthetic?
There's nothing wrong with standard motor oils in a motor. however, they do need to be changed every 2-3000 miles, making the synthetic have a real advantage in longevity.
Regarding instructions? The oil filer is located in a canister at the front of the engine, top side. You unscrew either a metal screw or larger plastic screw to change the oil. I think I actually have one of the large sockets I may never need again if anyone wants to buy it. I know 97 came tht way.
You will also want to purchase your oil filters from a BMW dealer.
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