it is an early 99 model, auto transmission (no idea what tranny it has, new to fords too, no just diesels.)...bone stock. btw, it is a swr truck.
The early 99 was the more important thing I was looking for.
The first thing to remember about improving fuel economy is to stay away from things like fat tires & lift kits. A truck that gets 18 mpg normally, with 35" tires and a 3 storey lift will only get maybe 10-12 mpg. While LT285/75r16may look better on the truck, skinnier highway treads like a LT235/85r16 will yield better mpg.
One of the changes that was made going from early 99's to the 99.5 was a change of PCM. They put a more powerful computer in the PCM which allowed for more refined programing. My early 99 had a very frustrating issue with the tranny programing. When I was towing, the tranny was very prone to dropping down from O/D to 3rd with every slight hill or head wind even though I'd have over half of the throttle pedal left.
I have to say, the by far, best mod I have ever done was to get a 99.5 PCM from DP Tuner with his 80hp Econo tune on it. When I swapped out the PCM's, the improvement was nothing short of eye watering. The amount of power increase was amazing. The tranny would now tow my camper up any hill in the area in O/D. Non-towing mpg improved 1-2 mpg on the highway. And as a little bonus, I now have a little green light on the dash that tells me when the cruise control is engaged. The increase of mpg is something that is sometimes hard to realize with mods. The increase of power makes it so much more fun to drive, some folks actually see a mpg decrease. The trick is to exercise restraint of the right foot. If you can do that, then some amount of mpg improvement is very achievable.
Other mpg mods will deal with improving the operating efficiency of the 7.3. From the factory, early 99's came with a catalytic convertor, but the 99.5's did not.
However, it seems like a lot of "cats" were disappearing, maybe it was due to the "high theft rate" of certain items containing valuable metals.
Enough said about disappearing "cats".
Many people will improve their exhaust by straight piping the factory pipe, putting in a Walker BTM (Big Truck Muffler), or installing a 4" or 5" turbo back system. I believe 3 1/2" is the stock size, 4" is the more common size of aftermarket exhaust and 5" is more for those with the more extreme horsepower mods.
A better intake system will help also. Generally you can find two styles of intake systems, open element & enclosed. The open element like Tymar and some of the AFE's to name two, are very low restriction. But an open element will draw in warm/hot air from under the hood which will cause the engine to run hotter. This can be an issue if towing during the summer. Believe me, I know.
A good enclosed type is the Ford AIS (Air Intake System). It has a real good filter element and fits just like it came from the factory. It has an intake snout that will draw in fresh/cooler air from the grille area. It works real well with the "Zoodad" mod which doesn't cost you any more than a few minutes, a hole saw and a hack saw blade. The one I settled with was the AIS with an add-on foam fender sleeve.
And finally, as with any mods, make sure you have gauges. In order of importance EGT, Boost, and tranny temp.
