Hey Ferm, or anyone that knows diesels

[spareparts]

from what Ive read on these models, an intercooler doesnt help much umless you go to a bigger turbo, and the bigger turbo doesnt help unless you get bigger injectors. Add it all up and I could buy a better truck for the money. Right now I'm just trying to get de ent power by bringing it up to speed and try to get a little better mpg out of it. 4wd drive conversion would just be for the fun of it. DP tuners seems to be the go to on software. Now, if I could only get the rpms down a bit. F250s run 355 gears and regulary get 17+ mpg. I'll see what kind of front axle I run across and go from there. The 6 speed swap and 33" tire would put me where I want to be, keeping the 5 speed and 35's would work as well

[THEFERMANATOR]

You should be turning around 2300 at 70 according to the gear ratio calculator. Going to the 6 speed would only drop you 130 RPM's at 70 MPH.

[spareparts]

I ran those numbers myself this morning, I guess the tach is off and my tires are short, still drinks fuel and sounds like its screaming at 70 mph. I couldn't get torque on my phone to work on the truck, speaking of which, you know any software(free) that may work, I do have a patch cable to plug into the OBD port from my computer, I'd gladly take that 130 rpm. The numbers work if you plug in 456 gears, I need to check the tag on the rear end, the door sticker says 410, but something isn't adding up right

[oteps]

I would spin the rear and check the gearing. Maybe someone changed it. did u replace the down pipe when u did the exhaust? Its the one between the firewall and engine.
U may be better off buying a rusted out 4x4 truck with the gears ratio you want to use for parts. we have a lot of them up here.
I have a 99 f350 7.3. I was getting around 18 mpg. haven't checked it since stage 1 injectors and chip.

[spareparts]

yes, I replaced the down pipe. I did some checking and found an exausht leak at the turbo, I've got a turbo seal kit on order, once it gets here I'll take care of that and see how it does. Just drove it back from Raleigh, ran 68 most of teh way, averaged 13.7 mpg. I'm going to hook up a boost gauge before I reseal teh turbo to see what kind of improvemt it makes. The enbine seems to be running rich. The new pipe is already black and I get a strong diesel smell when its running(I checked for fuel leaks, none found). Low boost would caause this. Need a software to run on my laptop to check the tach. Anyone tried "torque" with a diesel? I had mixed results running it on my old phone

[THEFERMANATOR]

From what I've read the torque app can be hit or miss. As to the sooted pipe, that is pretty well par for the course for a 7.3L. That is a DIRTY friggen diesel engine, and will haze even when in good condition. An exhaust leak at the turbo won't hurt your milage, if anything it would help it by lowering boost. When you're not running loaded, the less boost you run, the better the milage(more boost than needed is just wasted HP). It's sounding like you have either bad injectors, or a failing HPOP. Those engines normally get pretty good milage even stock, and the common causes of poor milage is injectors, or low high pressure oil pressure not allowing the injectors to properly atomize the fuel. Valve cover gaskets can also cause all kinds of problems like low voltage to the injectors, and not allowing them to run correctly. Theres a reason guys that work on those engines make BIG money, they always need work.

[oteps]

My truck is 1600 rpm at 55 and 1900 at 65 if that helps. its auto with 3.55 or 3.73 gears and 265 tires.
If u end up doing injectors do not buy from full force diesel. I have a set and am not happy with them. They send me a bad injector and cost me a lot of money that was not paid back.
You can have a hydraulic shop make up a hose and gauge to check the high pressure oil side. You can also make up a gauge for fuel pressure, mine has ports for pre filter and post. Im guessing u have changed your fuel filter lately?