I friend of mine has a 2003 F-250 with the 7.3L Diesel for sale that I am going to look at tomorrow. It has 75,000 miles on it, and I know it has had meticulous care (he is a retired heavy diesel mech...
BUY IT !!!!!!! I have FOUR 7.3 powerstrokes and love them. I pull my 30 foot fifth wheel with my 96 and my 99 trucks and I run a chip in the stock 99 which really wakes up the engine and improves towing. I run the Hydra chip which is VERY popular in the 7.3 for on the fly changing positions of the chip. The hydra chip will let you run stock, high idle, no start, tow, heavy tow and much more. For a stock 2003 with the hydra you will have more than enough power and improve shifting