Auto cars that don't have a dipstick for checking the fluid level, fill plug is usually located at left or right side of transmission. Their may be a drain plug on the bottom of the transmission. To check level, the car must be parked on level surface. When the fill plug is removed, some fluid should dribble out of the hole if the fluid is at the proper level (flush with the bottom of the fill plug hole). If no fluid comes out, add fluid to bring it up to the level of the hole.