My father has a 05 ccsb 6.0. He bought with 120k on it and 4 years later is has 165k. It’s bone stock with coolant filtration system. Mechanically it’s been perfect. But just based on the age of the truck things are starting to fail due to rust and age. He’s replaced bed rails, ac condenser, trans cooler lines, all 4 brake calipers, gauge cluster and driveshaft center bearing this year alone. So they can nickel and dime you. Which is why I bought a 6.7 instead of a 6.0.