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?
I have a 99 275hp 5.9 ISB pushing approx 20,000 lbs (4,500 more when towing), does just fine. Have climbed many hills w toad (Mammoth Mtn, Death Valley, Silverton, etc). I wouldn't worry at all about the 260 hp version on a 18k lb coach. BTW- I have the less desirable 4 speed MT643 trans, still performs fine.