Hello to all the DF members! I am new to diesels and have a line on an 07 Silverado 2500 HD ext cab. It has just over 100K on the odometer almost all highway miles up and down the east coast highways. Anything I should look for or be concerned about when I go look at the truck? It's supposed to be in Excellent condition and looks new ( my dad knows the current owner). Ballpark price range?