With about 13K miles, I am getting 9 mpg at best towing and have gotten 14.75 mpg running empty.

The truck is completely awesome for towing, steady as a rock even in high winds on the Interstate.

I am seeing PSD owners reporting somewhat better mileage than I am getting.

My dealer suggested checking the computer settings. I haven't had that done yet. I was also looking at the DynoMax 4 inch exhaust system and the Hypertech tuning module to change the computer settings. I am somewhat leery of that as I'm told the auto trans won't stand much HP increase.

I love the truck, but I'm a bit disappointed in the mileage.

As for you question, I know when new chips are used, usually the exhaust temp gasses need to be monitored. I've seen trucks using the Banks system, and they all had gauge pods installed, one of which showed the exhaust temperature.

Check out http://forums.ford-diesel.com/ubbthreads/ They might have a bit more info for you.

From the discussions on the Ford-diesel.com forums mileage seems to vary widely.

I have a late 2001 (August build date) F350 with the PSD/Auto. So far it has 3000 miles. I'm getting a solid 18 mpg highway, 16.9 all round and got 13.9 on my first tow with the race car (24" heavy steel open trailer )and that's with 4.10 gears.

The first thing I would do is have the pcm computer re-flashed. Ford has upgraded the program several times. The program controls the fuel curve and transmission among other things. There is a sticker on the inside of your driver's door near the top hinge with the current computer code. Mine has PMT3. If you have any kind of electronic engine work done Ford always updates to whatever the latest code is. No charge if you don't ask. If you do ask and there is nothing wroing it's about a 1 hr labor charge. But, since you have a 2000 model you are in luck. Ford has a Technical Service Bulletin out about the 2000 models. Lot's of complaints about mushy/slow shifts fromt he trans. Many guys on the other site have made this complaint and got the flash upgrade free under their warranty. These guys report much better shifts and somewhat improved mileage. It's worth a try.

One other thing to consider is the fuel blend. Depending on what part of the country you are in the mileage will vary depending on how the fuel is blended to keep it from gelling in cold temps. They mix #1 diesel in with the #2. I'm in Alabama, so not much #1 is needed.

Later,

I left out a couple of things.

I was told when I bought the truck by the dealer, who had driven it as his personal demo, not to tow in OD. That makes for some fairly high RPM on the hiway. Our normal week-end tow is about 130 miles each way on hilly 2 lane roads. I don't try to run in OD on those trips.

I have run in OD on the interstate when I can run over 70MPH. That keeps the RPM over 2000 which is where it seems to want to downshift.

Our Race trans. guy also does tow and heavy duty stuff, and he claims that the things get hot when the converter unlocks. I have purchased a temp guage, but haven't got it installed yet. I understand that is one of the things that can be reprogrammed with the HyperTech module.

http://www.crankandchrome.com/site/thisweek.php

What I found interesting was the segment on the PressureLoc Transmission Control

http://www.bd-power.com/ford/product.php?pn=PressureLoc%20Transmission%20Controls&tt=ford

"
1995-2001 Ford E4OD & 4R100 Transmissions. The BD PressureLoc plugs in
and increases your transmissions hydraulic pressure to hold the clutch plates
together to prevent slipping which results in over heating and premature wear.

Stock Ford automatic transmission pressures are not high enough at idle for
exhaust brake applications or at light throttle position for stock and modified
engine power.

Additional engine performance results in less throttle travel to achieve the same
vehicle speed which results in less hydraulic pressure that is holding the clutch
plates together. The PressureLoc increases the pressure every time the lock up
clutch engages. This increases the pressure applied to all the clutches in the
transmission.

Exhaust brakes engage when you have your foot off of the accelerator pedal and
this is when transmission pressures are the lowest. When the convertor lock up
clutch is engaged 100% of the retarding power can be transferred but the clutch
applied pressure should be increased with a PressureLoc.

This new state of the art technology has been designed to easily plug into the
transmission. It increases the pressure to a predetermined level rather than a
percentage increase over the present level. "

Interesting stuff. Thier power chips are higher priced than the Hypertech module, but preprogrammed, of course.

I think I'm going to start with getting my dealer to reflash the module and get the 4" exhaust.