For those of you that own or have owned a 2000 or 1999 F 250 diesel what kind of mileage have you managed? Any fuel saving changes or tips? I'm thinking about making the serious upgrade to a diesel if the price is right on the truck. Just curious as to actual fuel economy. Thanks.

 

most stock 7.3 powerstrokes get around 9-12 towing heavy, and 14-17 running empty. The trick is to keep your RPM's under 2000. Anything over 2000rpm is just waisting fuel with these engines.

With a few mods and intake/exhaust changes, you can get a few more miles per gallon out of the above numbers.

Anyone who claims more than about 23, is either runny an economy chip that makes very little power, or thinks his overhead fuel computer is accurate!! (I assure you, they are NOT).

 

or thinks his overhead fuel computer is accurate!! (I assure you, they are NOT).


You are right about that. They are the most inaccurate guage on the truck and only get more inaccurate when you change the settings with a chip/tuner!

 

It's hard to say what kind of mileage you will get. A lot depends on truck configuration (crewcab/supercab/regular cab, longbed/shortbed, and especially 4x4 or 4x2). My parents tow a 12K fifth wheel with their F350 dually 2wd and get about 14 MPG on the highway.

Another key to mileage is how you drive it. If you're up above 2000 RPM quite a bit and punch it when you accelerate your mileage will be significantly lower.

 

i own a 2000 SD, F-250, 4 door, long bed, 4" lift & 35" BFG;s with the 7.3, when it was stock before the programmer if i kept it around 65 mph & around 1700 rpm's i would average about 18-20 mpg. anything over 65 mph & over 2000 rpm's i'm gettin' about 12-15 mpg. i also live at 6500 feet above sea level, don't know if that matters?

 

I just purchased a 99 f-250 4 door short bed 4x4 7.3 turbo siesel. It has 285/r75 tires a super chip set at safe tow and 3" exhaust. I am only getting 12.8 mpg not towing anything. I just put a new k/N air filter on. any tips on increasing mpr? I stay under2000rpm and don't excellarate hard the truck has not been used for tow yet. It was owned by someone in the airforce who was sent overseas so his wife has been driving it for family transportation only has 75000 miles

 

Be careful with that K&N. they only work if the filter has the oil in it, and a diesel pulls so hard for air, that they will suck all the oil out of the filter pretty fast, leaving you engine as vulnerable as not having a filter at all. I would check it at every oil change. I love K&N filters, and have put them on almost every vehicle that I have had, the one exception being my 99 f350 7.3, just didn't think it would be worth the trouble of checking it every 5,000.

 

I will respond to two posts here. First I get on avg. 26 mpg and I do not use the economy tune with no HP I use the 60 HP from the predator with lots o umph. the key to better fuel economy is not the rpm's its the EGT. For those of you who have paid to put gauges on your trucks good call for many reasons. But for this reason too. Your truck gets the most complete combustion of fuel at 600 degrees that should be pretty close to crusing speed in all gears. yes it is about 2000 rpms but not always. Be back gotta 911 call finish later.

Fire Rooster

 

I'll be honest. I dont believe that 26mpg number. Is your truck an F-250, 2-wheeldrive, regular cab longbed? You would have to be, to get the truck to weigh as little as possible to get that kind of mileage. Also, have you changed the gears, or put on a taller tire? Is the speedo calibrated? Do you get your numbers via overhead computer, or hand calculating?

as for combustion temps, The only time I ever see it below 550 is idling around the parking lots. ANY cruising around is at or above 600. 65mph, empty running is 600 exactly. The faster I go, the hotter it gets since you need more fuel to overcome wind resistance.

I have only seen ONE documented PSD get better than 23mpg, and it was done as a test, utilizing the "under 2000 RPM" concept, and all the mods done for economy and not power. I say test, because the guy who did it said it was no fun to drive like that and went back to normal driving and was back to 19mpg in a heartbeat.

 

Sorry now I am back, Yes I do get 26 mpg. it is hand calculated and I run the stock tires and rims, no gearing changes and it is a CC, SB, 4x4. My odometer is exactly on according to my drive to work in miles. My wifes Toyota gets the exact same miles from my door to my work. Both of my motor cycles are within a tenth of a mile to and from work. Yes your Egt's are going to rise and fall with acceleration etc. but once you reach CRUISING speed it should level off at around 550 to 600 degrees. And between 1800 and 2200 rpms based on wind hills etc.

The whole K&N thing. Melisa is right keep it oiled up. It is ok to use but not with the stock air box it will not seal right and cause dusting of the turbo. Also get a precleaner on it too. It is a 25 dollar sleeve that fits over the K&N and makes cleaning the filter and oiling much easier. It also helps catch dust too. Now I know that some guys on here are very spiteful of K&N. But I nor all of my buddies who use them have had a problem as long as they got rid of the stock air box. We all us the Airaid intake to replace the stocker.

Fire Rooster

 

Man rooster, that is pretty impressive. Have you changed exhaust from stock? I got the biggest change when I got the Diablo tuner, and run it on 60hp or their "econo" mod, after the new wore off and my foot got lighter from the new found fun power. I tried the 40 or towing mode, but it did not do the trick like the 60. I have a 2000 4wd, and get 19 on interstate trips and usually about 16 on my normal driving 50/50 everyday town and interstate trips. I have boyz to haul and have to have the crew cab so it is the perfect truck for me...

 

spitball yes I have a 4 in exhaust turbo back. And yeah you're right it is a perfect truck. Sharp enough to calla truck and haul the family too. Plus all the power in the world to pull our toyhauler around full o toys.

Fire Rooster

 

Zombie - in response to your original question, +20 mpg would be unusual IMO. I have a stock 2000 CC LB 4WD and best I've ever got for mpg is 19.5. Pretty good for a vehicle that's "heavy" and "square". I recently made a trip to Texas and back and averaged between 14-15 mpg pulling about 5K lbs. My buddy has a GM CC SB 4WD with the 8.0 liter. He gets 10-12 mpg empty. He complains about the noise when riding in my truck, but doesn't have much to say once I show him the mpg on the overhead computer. I made the jump to diesel 2 years ago - I'll never go back!

 

thanks for the come backs. Is changing to a 4' exhaust worth the expence? If not the K/N air filter what is the best set up. I love my truck now I just have to school myself and with this wonderful web sight I have found new friends a the best source of info you could ask for Thanks!!

 

Blue water, there are many ways to go on the intake. I have used K&N on all my trucks, and just changed Friday and feel better about the truck. I had a drop in K&N, went with the NAPA filter setup, you can do a search on it if you like here and it comes with pictures. But the TYMAR setup is very nice, and reasonable. I would definetly change the stock. It takes 6 bolts and about 5 minutes to get that junk out of there, and drop in either the NAPA or Tymar. You will not believe the air difference. I don't know how the truck was running before with the stock and K&N drop in unit....