The 2004 BMW 645Ci useS5W-30 SAE synthetic motor oil and takeS8.4 quarts of it, which includes what's used by the filter. If You want the highest possible OEM match, You can buy Liquimoly Special Tec LL, part number 2248 2249 20124. It runs about $7.29 a quart, but will really give Your old beemer a boost in performance when You're driving it. Some benefits of using a synthetic oil is going to include a better viscosity index, which improves the fluid dynamics at varied temperatures, and seal conditioners to prevent leaks from swelling; important things on an older vehicle like Yours.
Pennzoil platinum EURO 5W-30. Having the same model and year, I have found this oil to have quieter start ups which is more noticeable in winter, 8 quarts. Also change ZF auto transmission fluid about 50,000 miles- not full flush if over 100,000.
Jessica R.
April 9, 2020
The 2004 bwm 645ci uses sae 5w-30 oil.
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