What type of oil does a 1998 BMW 318ti take?

I also own 98 318ti. Per owner's manual:BMW strongly recommends use of API SG/SH class oils. Select the SAE viscosity rating acording to the average seasonal air temperature. According to the chart, use 5W-30 for temps 50 to -20 degrees Fahrenheit, and 15W-40 for 20 to 80 degrees Fahrenheit and above. There's a pretty big overlap in the range, so as a general rule, I use 5W-30 in the winter and 15W-40 in the summer. Always use 100% synthetic - best value for money - can go almost 10K between oil changes - basically only need the two seasonal changes per year.