Was looking at an 04 silverado, diesel. 140K miles (good bad or average for a used truck) body is solid. This would make my first diesel truck, and was just wondering about general maintenance, and cost of ownership. and other helpful things I should know. I'm not looking to "roll coal" or tow invisible trailers. Just need a truck to tow a double axle full of wood, with a bed full of wood if needed for home renovations.