Craftsman lawn mowers use a serial number formula that reveals your mower's manufacture date. By locating the serial number tag on your machine, you can easily determine your mower's age. If you have the owner's manual for your mower, you can also check the date printed on the inside of the manual. This date should be one year after the mower's manufacture date. However, your serial number provides the exact date your mower came off the manufacturing line.
Locate the identification decal on your lawn mower. Craftsman mowers have stickers with a serial number and date printed on them. This tag is usually located in a protected area on, beneath or near the seat of the riding mower.
Write down the first six numbers of the mower's serial number. The first two numbers are the mower's month of manufacture. The second two numbers indicate the day of manufacture and the third two will signify the year of manufacture.
Use the Craftsman serial number formula to determine your mower's specific age. For example, if the first six numbers of your model's serial number are 031398, your mower was manufactured on March 13, 1998.