Don't think I've ever seen any JD equipment that was modified for use in the oilfields.
Several years ago while on a fishing trip I spotted an old oil field. At least one of the derricks was still standing. There are several old trucks and all kinds of various pumps left on the property. My curiosity prompted me to turn onto an old gravel road that runs past a small metal building on the front of the place. Two old tractors are sitting near the building. It wasn't until later after the frosts had killed the grass that I was able to spot a third tractor. These are not just regular farm tractors. Each has an enormous winch mounted on the front. The front axles and wheels had to be relocated to accommodate the winches. They are Case tractors, but am not certain of the model or year. The rear metal fenders are what easily identifies them as being made by Case.
I located the actual owner of the property,but learned that an oil company has leased it since the 1950's. Have tried contacting them to see if a person could purchase the tractors, but never got a response.
There was a bad wildfire in the area a couple years back. I was concerned that the fire had consumed the tractors, but some friends who own a nearby farm said that the fire stopped just short of that property.