Looking at a 260 hp 5.9 Cummins in a super clean 2001 Expedition 34N that weighs 18400 dry. How much of a slug is this setup and will the transmission hold up to more power?
The 5.9 while not a power house is ok but the limiting factor is which transmission you are getting. 2500 is good but cannot handle more torque/power. Six speed will keep engine in better power range on grades. Another concern is the VP44 fuel injection pump. Cummins had a lot of bad pumps and the electronics are prone to failure from over heating.