John Deere zero turns, lawn mowers and riding mowers all have their serial numbers located on small black tags on the exteriors of the vehicles. The exact location of the tag varies depending on the type of John Deere vehicle.
The serial number for a John Deere riding mower is located underneath the driver's seat or behind the driver's seat on the green frame. The serial number for a walk-behind lawn mower is located on the upper-left side of the mowing deck as viewed from the back of the mower. The serial number for a zero turn lawn mower is located directly underneath the seat, which needs to be lifted up to reveal the serial number tag.