Fuel mileage

[jwduke]

Yes, beware of some of the milage claims here. I saw one earlier this AM, claiming 28 mpg. I have 1850 miles on mine, and I'm getting a little over 16, hand calculated

 

[Diesel4Stan]

I have noticed that if you coast alot(less braking) you will better numbers. Try it out it seems to work.

For fun, I was on a slight down hill, reset the mpg on the overhead and coasted for about 1/4 mile ---->> 44 mpg :-laf

Now, if I could get that on the highway all the time, I would be in heaven

 

[Turbo_Bob]

I averaged 9mpg or so. considering the 4. 10 gear and only goin 65

I feel the truck should be getting more than 14 empty the dealer told me that it should get about 20 at about 10k but i'm not getting close even though I baby it and try to keep it about 70 to keep the Rpm's down.

I drive truck for a living currently and I thing 2500 rpm's at 75 in the big hole is way to fast it should only be around 1800 at most the cummings can pull a lot at those rpms and get better mileage. I wish I had 3. 73's but with the weight it helps to get started with the 4. 10 they need to add another gear so the motor dosn't have to work so hard.

by the way the truck pulled that 25. 5k load back and didn't go under 4th gear of 50mph cummings 600 rocks :-laf

Pulling that kind of weight you need the 4. 10, you would be in third gear if you had the 3. 73

14 to 16 mpg solo with the 4. 10 and 325/600 engine is around the norm.



I have a 03. 5 305/555 engine 6 sp transmission and 3. 73 R&P. I get 21 mpg at 70 mph consistantly solo and the truck weighs 7000 + pounds with driver & fuel.

When I pull my 7000 pound enclosed trailer (14,000 GCWR) I get 13 mpg at 65 mph. One thing that I do notice is if you go beyond 70 mph the fuel mileage suffers.

 

[Slicks]

I've been babying mine driving Corona to Escondido on the 15 and have an average of 21. 9 on the the last 3 tanks. Mine is a 05 610 4-door Dually 3. 73 48re with a better muffler and an AFE intake. I am pretty happy, but it is killing me to let all the other Diesel's and Rice rockets pass. A month ago I would run 90-108(damn speed limiter) and got around 17. 5.

 

[RJOL]

With just under 1800 miles I'm getting 11mpg towing my 12K 5th wheel, and just over 16mpg empty (freeway - 60-65mph). Stop and go I'm getting around 14. 9. Hope these numbers improve, but if they don't... I'll just learn to live with it...

 

[testraub]

I've been testing a mileage program box for SP Diesel. had to make a run from Arlington, VA to East Aurora, NY this past weekend. with the box OFF and being gentle on the ride up (2K RPM 65-70 MPH) I got 15. 2 MPG. With the box ON and a bit heavier with the foot (2200 RPM 75-80 MPH) got 16. 3 MPG. Thats all hand calc'ed. Feel free to contact them at http://www.spdiesel.com/ and tell 'em "Tom sent me!

 

[OT-OF-HERE!!]

The key is,...

I haven't even towed enough in one complete tankful to figure it, but empty, w/ th 4. 10's and the auto transmission, I get an average of 11. 7mpg mostly hwy, little in town driving, so good luck. I seem to have the worst mileage that I've heard about though, and despite what you think, I AM babing it! Try to keep under 65 on the hwy is what I do to keep it UP around 11. 7mpg. I can get 12's if on flat ground hwy around 50/55mph!

IMHO the key to your poor mileage is in your first few words,... "haven't even towed enough..... ", That's a serious work truck you have and it's meant to work and the gears you have are for serious work. You need to find somebody with a Bob Cat (a big one) and strap it on and take it for a few hundred mile trip with some good inclines. That truck isn't broke in and until you work it, your mileage will probably stay stink-o for some time. Also your power will increase following some good breakin.

 

[DDiMarco]

My 325/600/3. 73's gets about 17 combined with 9500 miles on the speedo. The fact of the matter is if you stick your foot in it at all, you will pay for it. Any highway driving over 2000 rpm and your mileage will decline. I think with more break-in miles and steady highway driving, I will be able to approach 20 mpg. Half of the mileage issues I read about are probably the result of not knowing exactly how much fuel is in the tank to start with. Without the tank vent kit installed, the accuracy of the volume one calculates mileage with is directly proportional to the amount of patience used when filling up!

 

[2Gen3Gen]

 

[MRutledge]

Thought I'd chime in here. My 05 2500 is getting better milage than I expected, and the same or better milage than my '95 Cherokee that I had before the CTD.



Since purchasing the vehicle in December, my best milage has been about 18. 95, the worst was 13. 46, and a calculated average of 16. 66. 13 of the 24 fill ups (8338 miles) have 16. 5 or better. Most of this has been winter blend fuel, and cold, windy weather, as well as driving around town and me not being able to resist the urge to apply all 610 foot/pounds of torque.



I haven't noticed much of a milage difference using Stanadyne performance additive.



(Of course all standard milage disclaimers apply. I don't fill up at the same pump every time. I don't fill to the same point in the filler neck every time. YMMV, etc. )



-Matt