I would say use the 7.3, but use the turbo too. One of the service trucks I drove, an 88 F350 SD with 7.3 and 5 speed just was not stout at all, even though I had turned up the fuel press all I dared to. Threw a rod at 230,000. A racer friend had a 88 CCdually F350 with the 7.3, it too threw a rod. He bought an F250 that was totaled in a tornado near his home that had a 6.9 with the Banks turbo kit, installed it into the dually and it did a fine job pulling and fuel milage wise, better than the 7.3, but as stated, the 6.9 was puffed, the 7.3 was not.
As far as the Cummins, by the time you find one (if you find one), buy it PLUS the kit to install it, moneywise you would be better off trading for a Dodge. However this is just my opinion.
Man told me that a Dodge with a Cummins in it is like having a candy bar wrapped in ****. I aint no fan of a 5.9, we (Ryder) had thousands of them in the 90s in F700s and to me they wernt nowhere near the motor the 6.6 Ford was that it replaced. Again JMO.
Bad Company Till the day I die!
Last edited by bcr466; 07-10-2009 at 07:34 PM.