Is there any way to refill the transmission fluid in a 02 C240? I didn't see anywhere to fill it?

The fluid is filled through the dipstick tube. This is the tube that has a cap on it that says "MB Workshop Only". On your vehicle it is located at the back of the engine (the air cleaner will need to come off) next to the Mass Air Sensor. There is no dipstick when you take this cap off as it is a Mercedes Special Tool.

Will Stahnke
BenzTech1

how do I get the air cleaner and the big black cover off?

The air cleaner assembly comes off by simply pulling it upward. The cover in front comes off by lifting up and then pulling it toward you.