Many years ago when I was a 18 year old and working at a parts store a young lady came in looking for spark plugs for a 4020 john deere diesel. Husband sent her to town, next stop was to change winter air to summer air in her tires. Nice husband. Told her what was happening, she went home with 6 cheap plugs and a phony bill for $200.00. Sheepish husband returned the plugs the next day
