I gave 13k for my 2008 Chevy Silverado 2500HD 4x4 6.0 regular cab a few years ago with 27k miles on it and I've been ecstatic about it. Im nearly to 140k miles and tie rods have been my worst problems it eats Moogs once a year but it has 305/70r16 load range e tires that contributes to that. I've never had an issue out of the drivetrain until this month but it was a blown trans cooler line. My only complaint is its lacking on pulling power imho that engine belongs in a car all the power is in the upper rpm range. Although it has always manage to pull the loads the heaviest of which was 6 tons of gravel in a 20 foot tandem dual dump trailer. 13k seems high to me for the mileage unless you can verify the condition of the transmission