how many quarts of oil does the mercedes C280 (1999) take and should it be synthetic?

it should be in the owners manual. you really dont need synthetic oil except for high mileage. just stick with some good valvoline or castrol 10w-30 it will run just fine

Check your owners manual. There will also be the manufacturer requirement for the oil in there somewhere. Doesn't tell you much but if you google it you should be able to find out what type of oil you're suppose to use. conventional will work, but it doesn't mean it's suppose to go in there. If the engine was designed with hot points where the temperature exceeds 240 degrees the oil can break down if it's conventional. Additionally if the engine has small oil passages it may need synthetic for proper lubrication to avoid excess wear and tear.

8.25 quarts, Mobile 1 0w40 full synthetic Mercedes recommended

it takes about 7.5q you should put Mobile1 0w-40, it will make it run like a beauty! and its Mercedes Recomended. i have a 95 C280, and i am using Mobile1 0w-40 for the third time since i bought it in 2006. after i used Mobile1 it ran better than the other oil that the previous owner used. but make sure you put synthetic always since the car is getting old, you want to make sure you keep it well. try not to use Mobile1 high mileage or any other high mileage oil. 0w-40 will do very fine.

The owner's manual I believe does say 8.25 quarts but that is too much. It is more like 7.5. DO NOT overfill these engines. You WILL blow out the front crank seal. Also- Amsoil is the best oil you can buy. I've used it since 1978 in cars, motorcycles and snowmobiles. I use 5-40 European in my C280.

7.9 quarts is the correct answer for a 1994 c280