* 4R70W: Capacity is approximately 11-12 quarts including the torque converter.
* 4R100: Capacity is approximately 16-18 quarts including the torque converter.
You absolutely MUST determine which transmission you have before adding fluid. Checking the transmission identification tag on the transmission itself is the most reliable method. Your owner's manual might also list the transmission type.
Do not simply add fluid based on an average. Overfilling can damage the transmission. The best approach is to perform a drain and fill, or better yet, a complete transmission fluid exchange at a professional shop. They will have the correct tools and procedures to accurately determine the fluid level.