Have F250, seeking better mileage

[NedTheHead]

Hello folks!

I recently purchased a 1999 diesel F250 (2WD, auto, longbed) to haul my home--a 5th wheel RV, but it will soon be my only vehicle so I'd like to make it less of a money sink to drive around town when it's not towing anything.

I've already removed a lot of heavy junk that the truck came with like the front ramming grille (lol), step bars, toolbox, and the conventional rear tow hitch. It's time to move onto the next thing but I'm not really sure where to start, and I don't want to spend a lot more money improving its fuel efficiency than I'll reap in fuel savings since I'm not a really heavy driver (< 10k miles/yr). Also I am just a cheapskate in general. Can you say Saran wrap tonneau cover?

The truck came with a Bully Dog programmer which shows MPG, but I'm pretty sure it's miscalibrated since it showed like 40 MPG on the highway drive home. I hand-calculated closer to 20. Do I need a scangauge, or will this thing do the trick?

Thanks, everyone!

[rmay635703]

There is no fuel economy instrumentation available for diesels, unless you use the old manual thing from the 80s.

The scanguage will calculate FE on a diesel once calibrated so long as you drive one speed with one throttle position, deviate a little bit and the thing is WAY off.

[cRiPpLe_rOoStEr]

Have you ever considered a Cummins swap (a.k.a. Powerstroke delete kit )?

Anyway, an F250 is really heavy. BTW which cab does it have?

[NedTheHead]

Originally Posted by cRiPpLe_rOoStEr

Have you ever considered a Cummins swap (a.k.a. Powerstroke delete kit )?

Anyway, an F250 is really heavy. BTW which cab does it have?

Heh, I think a "Powerstroke delete kit" is a bit rich for my blood.

It has a SuperCab and it's really not all that heavy compared to the competition. When I got it, the previous owner had it weighed on a public scale and it clocked in at 6,400 pounds and some change. That was before I removed the ramming grille, step bars, bed toolbox, and conventional rear tow hitch. I wasn't able to weigh those things or the truck since then but they certainly felt like they added about 300 pounds or more! The fifth wheel hitch is about 110 lbs. So on balance, it should still be under 6,400.

I was looking at the vehicle stats of Diesel Dave and Big Dave, and their trucks weigh in at 6,350 and 7,900 lbs, respectively. Big Dave's "Red Baron" 2000 F350 is listed at 26 MPG, and it's basically a larger, heavier version of my truck. And Diesel Dave's 32 MPG CTD Ram blows my mind! Is the Cummins engine really that much more efficient than the 7.3 PSD? Our trucks are nearly the same weight!

[ttsupra2503]

Originally Posted by NedTheHead

Heh, I think a "Powerstroke delete kit" is a bit rich for my blood.

It has a SuperCab and it's really not all that heavy compared to the competition. When I got it, the previous owner had it weighed on a public scale and it clocked in at 6,400 pounds and some change. That was before I removed the ramming grille, step bars, bed toolbox, and conventional rear tow hitch. I wasn't able to weigh those things or the truck since then but they certainly felt like they added about 300 pounds or more! The fifth wheel hitch is about 110 lbs. So on balance, it should still be under 6,400.

I was looking at the vehicle stats of Diesel Dave and Big Dave, and their trucks weigh in at 6,350 and 7,900 lbs, respectively. Big Dave's "Red Baron" 2000 F350 is listed at 26 MPG, and it's basically a larger, heavier version of my truck. And Diesel Dave's 32 MPG CTD Ram blows my mind! Is the Cummins engine really that much more efficient than the 7.3 PSD? Our trucks are nearly the same weight!

To sum it up... yes.. they are that much more efficient and that much better of an Engine. They produce more torque which is needed for pulling trailers and getting that mileage that they get so often. One of my friends owns a 2001 dodge cummins 24valve duelly 5 speed. He gets over 30mpg while still having access to over 1000ft lbs of torque. I remember the day he towed a 50 foot barge up onto the shoreline with his truck.

Depending on what you want to do, you might consider going to a toyota tacoma. They do most everything a larger truck can do (tow 5-8 thousand pounds) while getting 9L/100km when empty. You are gonna pay money for them.. I see them up in Canada at around 14 thousand dollars. I drive the 4runner version right now but will be switching over later this year. I have hauled 6500 lbs like it wasn't there and the truck has a 5 speed auto and a better rating. If your hauling more weight you should stay with the diesel.

ps. gas is cheaper up here then diesel and gas can be converted to LPG which is .79 c a Liter.

[DieselX]

The Power Stroke is an electronically controlled, direct injection engine with a 4.11 in (104 mm) bore and 4.18 in (106 mm) stroke creating a displacement of 444 cu in (7.3 L). It has a 17.5:1 compression ratio, and has a dry weight of approximately 920 lb (420 kg). This engine produced up to 250 hp (190 kW) and 505 lb·ft (685 N·m) of torque in automatic-transmission trucks during the last years of production, and 275 hp (205 kW) and 520 lb·ft (705 N·m) of torque in manual-transmission trucks.


Midway through model year 1998, the Dodge Ram switched from the 6BT to the ISB to meet updated emissions requirements. Like other ISB's, these engines started out using the Bosch VP44 rotary injection pump. The VP44 setup meant that timing and fuel could be precisely controlled, which led to cleaner emissions. However, VP44 failure rates were very high versus the older P7100 injection pump. The compression ratio in these engines was 16.3:1. The 1998–2000 ISB was rated at 215 horsepower (160 kW; 218 PS) and 420 pound-feet (569 N·m) when equipped with the 47RE automatic transmission. The 1998 ISB was rated at 235 horsepower (175 kW; 238 PS) and 420 pound-feet (569 N·m) when equipped with the manual transmission. The 1999–2000 ISB was rated at 235 horsepower (175 kW; 238 PS) and 460 pound-feet (624 N·m) when equipped with a manual transmission. For the 2001–2002 model years, a standard output and high output ISB Cummins engine was offered. The standard output, which was the same as the previous engines was rated to 235 horsepower (175 kW; 238 PS) and 460 pound-feet (624 N·m) when equipped with either a manual transmission or automatic. The high output ISB was rated at 245 horsepower (183 kW; 248 PS) and 505 pound-feet (685 N·m), and only a NV5600 six-speed manual transmission was offered behind it. The high output engine was different in a few ways from the standard output engine. The high output ISB had higher compression (17.1:1), powdered metal valve seat inserts and a larger flywheel. The Bosch fuel system was reworked as well to allow increase fuel delivery and a slight increase in timing. Also in 2001 a new cam gear was introduced thus eliminating the need for a crank position sensor on the later 01-02 models.

Compare the same years theres not much difference in power or torque.

[NedTheHead]

Getting a different vehicle or swapping out the engine aren't options for me. I got a screaming deal on the F250 ($6,500 OTD) and don't want to spend several thousand dollars on a different engine or twice as much as I paid for my current vehicle on a less capable one that won't meet my needs (towing > 10,000 lb fifth wheel several times a year). None of that would make any sense $$$-wise even if the MPG were a bit higher. What I'm looking to do is eke out more efficiency from the truck I already have. I love the Cummins engine as well but let's not start a diesel engine flamewar.

I was more looking for other suggestions that are perhaps less extreme or expensive.

[2000mc]

How about a bike, moped or small motorcycle that you could haul on the back of the rv

[ttsupra2503]

I would open up the intake and exhaust for a more free flowing setup, block off the front end for better aerodynamics. A controller for the engine that allows power and eco modes helps as well.
In the end the fuel costs are not gonna be cheap with this motor or setup due to design. Not bashing anyone, just the truth

[MetroMPG]

Best return on investment is to adjust the nut behind the wheel.

Have you studied the 100+ hypermiling tips (linked at the top of the page) to see which ones apply to your driving regimen/environment?

Sorting out a fuel economy display that does instant & resettable trip avg is a must. You can't manage what you don't measure, and going tank by tank isn't fast enough feedback.

After that... the saran wrap aero cap sounds like fun!

Welcome to the forum.