I have an 05 auto with a little over 90,000, and have never needed to do anything to it.  I change the oil every 10,000 miles, put fuel in it and drive it. Consistantly get about 40 mpg with zero driving for fuel mileage. I have been debating whether to keep it for the long haul, or trade it for an 09 TDI or gasser. Wish diesel prices were where they were when I bought it! 
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1999 F250 SD CC V10 4X4 4" Superlift 35"BFG's, Bilstein 5100's, American Racing Wheels, Borla dual exhaust, chip, K&N Gen II air filter system
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