1. Literally, on or via a vehicle with wheels, such as an automobile, bicycle, or motorcycle. Our family is getting ready to do our move on wheels across the country. Neither of us had seen much of the countryside, so we decided to have our next date on wheels.
2. Very smoothly; without difficulty, problems, or hindrances. Dinner service was running on wheels until an entire sauce pot fell off the stove.
3. Used as an intensifier of something as being difficult, unruly, unpleasant, disliked, etc. There's this one guy in our department who is a real jerk on wheels. It's like he enjoys making other people upset!