hello, im new to the site but i own a 1997 F350 crew cab long bed 4x4 with a 7.3 that starting to get really old its got about 394,000km and starting to have problems its been a work truck all it life dirt roads ete.. and now i want to have more power and better fuel economy i average 14-16mpg witch is still not bad but i know i could do better the 7.3 has been true hell and back and will gladly say its the tuffest engine i ever Sean but i don't know yet if i should do a swap

Engines im considering

ISB 5.9 24valve 1998-2002 with dodge tranny

ISB 6.7 2007-present with dodge tranny

or keep the 7.3 but start modifying it right now its bone stock small amount of blow by but still life in it

if i go with the cummins swap i thot using a 6.0L intercooler the 7.3 radiator and try to keep as much as possible from the original engine, im a welder so i could fab some stuff my self, i plan on towing and lots of highway and i live in the city i currently also have 4.10 gearing , but might also do a 05-07 superduty axle swap to 3.55. i dont have a budget and i don't want a new truck i love my obs but could uses a bit of new under the hood, im going to school again for heavy equipment mechanic and mechanical engineering so this project will help me with this, so wat you guys think and can you give me ideas to wat to mod/upgrade/watt to look fore , i have ben looking all over online and not much help for wat i want to do , diesel world i think did this swap but didn't give much info on it so wat you guys think

 

First of all, welcome to the site. Do a compression check and see what you have before you consider a swap. Even if its not the greatest compression, they will run a long time. What you see in my signature, I have between 350 and 375 compression and it pulls what you see. But I've done a lot of mods to get there.

 

Six in a row makes it sloooww


8in a v makes it go weeeee


You are in a PSD forum...is there any other answer...

 

Welcome to FTE! I have a crew cab project truck that originally started as a Cummins swap. It was a 460 gas truck and I got a good deal on the Cummins, but before I ever started working on it, I got a hold of a 7.3 and sold the Cummins. I would stay with the 7.3. I think you will be happier with it in the long run, and not near as much work. The time and money you would put toward the Cummins swap could go toward bringing new life to the awesome engine you already have . As far as the axle swap goes, the Superduty axle swap is fairly common, but they have 3.73 gears. You mentioned 3.55s in your post above, and you can get those in an OBS axle. The only two ratios offered in the OBS trucks were 4.10 and 3.55. If it is the 3.55s that you want, then that will save you a lot of time and money also. The main benefit I see of the SD axle swap is the rear disc brakes, but you can convert a 10.25 Sterling to disc brakes also. Which ever way you decide to go with this project, good luck and keep us posted.......and lots of pics!......we love pics