That will make an awesome gift. The old 6.9s run forever, but they don't have enough horsepower to get out of their own way. That makes it good for a young driver.
I have a similar issue with a 2013 Chevrolet Suburban. At 35,000 mi it started using oil (3 + quarts in 5,000 mi). We took it to the dealer to check it out. After all was said and done and 10,000 more miles, Chevrolet ended up replacing all 8 pistons and rings. The service representative...