4x4 fuel mileage

[Archive]

ROCK KRIES,
I've seen my trip computer range from 0. 2 OVER my actual mileage, up to 1. 5 UNDER. Most often it is about 0. 5 to 0. 7 under. But consider this: Your mileage, calculated the old way, can be off by more than 1 mpg just because at station #1 you parked on a left-slope while at station #2 you were on a right slope, or, because the fuel foamed more that day or you filled it all the way up the neck. Also, errors will be greater on "partial" tank fill ups. If you only bought ~$10 worth, then $0. 50 more (an amount I can always squeeze in by waiting for the foam to subside) represents a 5% error in the calculation. On a $40 fill up, this same extra $0. 50 only causes a 1. 25% error. Given all the potential sources of error, I feel at least some of the error we all see on INDIVIDUAL fill-ups is really in our CALCULATED mileage, and I don't think it is fair to assume it is always totally "computer" error. That said, if you average over several tanks, or hundreds of miles, then the manually calculated mileage is going to be very, very accurate.
I find that the real value of the trip computer is not for calculating the mpg at the end of the trip. What makes it a valuable gauge is the "instantaneous" readings that allow you to fine tune your driving style to maximize mpg. If yours generally reads a little low but is consistent, I would not worry about getting it calibrated. It's not worth the risk of letting someone else under your hood!
JOMO

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2001 ETH, QC, LWB, 4WD, 3. 54, SPA Pyro & Boost, Leer Cab-high shell, ARB's soon

 

[Archive]

HC, you are right about not letting anyone under the hood to mess around trying to re-calibrate. I do know when I run the truck to 10 miles DTE and 1/8 tank left, to fill takes 27-28 gallons. At least I know I will never do the dreaded out of fuel thing!!!!!

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THE ROCK/2001,4X4,3. 54 GEARS,QC,SB,AT,SPORT,CL,CAMPER PACKAGE,TRAILER PACKAGE,WHITE,MOPAR MOLDED SPLASH GUARDS,STEELHORSE NERF BARS,BEDRUG LINER,CAB HIGH CAP.

 

[Archive]

Hummm, now I wonder:
I've seen 0 miles DTE, and like Rock Kries I had some "real" miles left. If I had kept driving, would it have stayed at 0, or done something interesting like flashing negative numbers?
Question #2: Is answering question #1 worth the risk of running out of fuel? (curiosity killed the cat)
RK, I think you're right - they probably set the DTE feature to go to zero WAY before you really run out, just to help save customers the grief. Also, imagine how we would feel if we stalled at 5 miles DTE - we would jump all over their butts - so, DC set it up conservative and saved both sides the grief!

 

[Archive]

Just drove across the country (VT to MT). MT we were doing 75+, otherwise 65ish. I averaged just over 18mpg. AC on the entire trip. (88degrees at the top of the 'road to the sun' in Glacier National Park)

With DDI's,DD elbow and Power Edge. 3. 54, 5spd, stock tires, hit 20K on the odometer.

No front airdam, cabheight cap, #700 load plus wife and myself.
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Will track mpg again on the way home next week. Back to the waverunner for now... !!

 

[Archive]

Have 1500 miles on my truck so far, and doing the math by hand I get 13. 4 all city driving. Computer on mine reads perfect.



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2K1 3500 4x4 SLT+ QC ETH/DEE

 

[Archive]

Well, heres something that has surprised me.
My last tank of fuel was all hwy, no trailer.
I cruised at 2,000 rpm as often as I could.
I got 23. 8 mph by calculator.
The trip computer showed 24. 2
Thats with a few mods on this truck.
3500 4x4 ETH #ad


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My Site

[This message has been edited by scott1 (edited 07-15-2000). ]

 

[Archive]

HC, You are probably right about the conserative set up. Knowing that I still have about 7 gallons left at 10 DTE I am going to go to zero and see if it does go to negative numbers.

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THE ROCK/2001,4X4,3. 54 GEARS,QC,SB,AT,SPORT,CL,CAMPER PACKAGE,TRAILER PACKAGE,WHITE,MOPAR MOLDED SPLASH GUARDS,STEELHORSE NERF BARS,BEDRUG LINER,CAB HIGH CAP.

 

[Archive]

I've been getting 23+ for a while. This is "around town". For me this means back country roads at about 40-50mph.
Highway I get about 20. 70-80 mph, unloaded.
Last time I towed, was a 5000 lb camper, cruise set on 80 all night. Got 12 mpg on the way there (big head wind), 13 back.
I don't baby it, I know there is another 1 mpg in it.

 

[Archive]

I've been getting 23+ for a while. This is "around town". For me this means back country roads at about 40-50mph.
Highway I get about 20. 70-80 mph, unloaded.
Last time I towed, was a 5000 lb camper, cruise set on 80 all night. Got 12 mpg on the way there (big head wind), 13 back.
I don't baby it, I know there is another 1 mpg in it.

 

[Archive]

18 to 19 in town, and a round trip From Phoenix to Tucson About 100 miles each way, empty 20. 5 average. Speed 75 to 80. Slightly uphill to Tucson.

On a trip to Pinetop and Back Apx 200 miles each way Pinetop is around 7000ft / Phx 1600ft, the way up 17. 3mpg, down 24. 6 both ways 65 and empty.

Sounds like we're all about the same.

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99' Quad Cab, 4x4, Auto, 3. 55, All options except fog lights and leather, Glasstite topper, Chrome Nerf Bars, VA CPC, DiPricol EGT & Boost Gauges Pillar Mount, K&N Air Filter, Turbo Silencer Ring Removed

 

[Archive]

My milage varies very little loaded or empty.
22. 8 Hwy, 18. 6 City Just makes me love the Cummins more and more. #ad
#ad
#ad


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99 2500 Quad 4X4 Black 5-Speed
Cummins Longbed

 

[Archive]

<font color=blue>Just went on a 2000 mile trip to Texas and back. Averaged (by calculater) 17. 5 mpg. That was driving 70 to 75mph and playing alot running upto 90mph and such. I now have 5400 miles on my truck. I consider it acceptable with the 4. 10 ratio I have.

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• <font color=blue>
• Eric D. Howard - #ad
  - BOMB'er! - #ad
  - TDR Member since April 8th, 2000
• 2001 Dodge Ram 2500 HD 4x4 SLT Auto Reg cab Cummins Turbo Diesel 4. 10 gear ratio LT265/75R/16 tires
• Patriot Blue Pearl Coat, Agate interior, Leather seats EVERY option, Silencer Ring AWOL</font>

[This message has been edited by KatDiesel (edited 07-17-2000). ]

 

[Archive]

I towed my 24 ft bumper hitch camper this weekend and got 12. 50 mpg on that tank of fuel. Shouldent it do better than that. I drove between 65 and 70.

 

[Archive]

I get 16-18 mpg in the city, but i spend a lot of time with the air on and idling. On the highway i get in between 22 and 24 depending on if i am running above or below 75 mph. Hauling a 20k load i get about 18 on the highway at 65 - 70 mph. Nick

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1995 Dodge Ram 2500, 4X4, White, Auto with Performance Torque Converter, lock up switch, 3. 54 gears, Psychotty air filterong system, Silencer ring in the garage, Banks Power Pack, with Pyrometer and boost guages in pillar mount, No cat or muffler, 3" exhaust exits behind rear wheels thru 4" X 20" chrome tips, Go Rhino nerf bars, Wild Cat Flash Brush/Grill Guard with 2 150 watt 6" Eagle One lights tied into high beams, 5% tinted windows, Pioneer DEH 7200 CD player, 6 disc CD changer and 2 Memphis 3 way 6x9's and 1 Kove 12" with a Crossfire 404 amp, IDelta aluminum toolbox, Dodge bedliner, Heckethorn Nitro 9000 shocks and dual steering stabilizer, 16 X 8 Eagle Alloy rims with 285/75/R16 B F Goodrich All-Terrains, New bed, front fenders and paint job due to some vandalism