fuel mileage?

[GregTaylor]

if i don't go past 55 mph and accelerate extreemly slowly i can get 23 mpg from thousand oaks to santamonica calif 40 some miles round trip. man it takes real patience to go that slow in la traffic. but if i drive like a true califonia and weave like a beemer with a spliied late ill get 17 mph. and thats on the trip computer. ive caculated the millage with the caculator and there was a mile or 2 to the gallon off on the trip computer real numbers were in the 16 range and the trip computer was in the hi 17's.

03 larame 2500 4x4 so and the 3. ?? diff

 

[BHolm]

My '03 QC 4x4 shortbox Ho auto just crossed 10k miles. I reset the trip computer and took a short road trip with the truck empty. I averaged about 17mpg. When towing, the truck is averaging 11 mpg, that was for the first 10k miles. Not too bad but, not 20 either. I suspect that the light bar on top, running with the tow mirrors out and cruising at 70-75 is what brings it down.

 

[y-knot]

I think there are alot of exagerated claims made by the diesel world, I think alot of people do that to justify there purchase, you know , the extra 5000-6000 dollars for the diesel. When because it's not the norm, and most people don't get the whole diesel thing anyway, you exagerate some on the fuel mileage. They might not get the whole diesel experiance, but they will understand good mileage numbers. And it's always fun to mess they the guy who bought a V-10, or now HEMI, they are strugleing with there 8 MPG, and it's fun to tell them how you are getting well over 21 MPG. That puzzeled look on there face is priceless.

 

[Bertram65]

Best I have seen is 17. 6 MPG averaging about 16 MPG over 4500 miles all calcuated by hand. Most of my driving is mixed 50/50 city and highway, towed once for 80 miles, 5K lbs.

I drive about 68-70 MPH on the highway, having the 4. 10s and not being in a rush I rarely go above that. I cannot imagine I will ever see 20 MPG, truck is a 4X4 SRW QC SO 48RE with CA/MA emmisions. I happy with the mileage, I was not expecting it to be any better.

 

[Steve M]

And thus spake Hudsonhawk,

Okay, what did you do to the D to get 20MPG? The best I averaged was 16 to 17 MPG with mine on the freeway. 01 4. 7 3. 92 FT4WD



We have a 2WD with 3. 55 ratio. Keeping the rpm under 2000 makes a big difference with the 4. 7 and the Cummins. I also keep the tires aired up to max on the sidewall. The D getting one mpg better than the C highway is no surprise to me. It's much smaller and is geared for mpg. My Cummins is geared for towing. If I set the cruise on 55mph, I get 23mpg on the trip computer with the Cummins but I can't stay awake. For the past couple of weeks I've decided crap on mileage. I've been enjoying the power of the Cummins and the 4. 7. That's why I bought them. Not so I could worry endlessly over 2 or 3 mpg out of a 7200 lb truck and SUV with a thirsty sweet sounding V8 under the hood. They're both fun to drive towing or empty!

 

[BVK]

Milage vs speed

I have records from the beginning to 3300 MI on the stock TD. It look so me that the milage would be 19 at 80 MI/hr and 22 at 60 MI/hr. Here are the numbers:

0

29----20. 7

269--22. 5

774---21. 0

1077--22. 2

1597--21. 0

2084--20. 4

2446--20. 4

2921--19. 9

3268--21. 0

for overall avg 20. 9 MI/gal. No load, tot. average 44. 4 MI/hour of engine operation - several long trips.

I have to start recording engine hours at each fill, I bet there will be a good correlation between milage and MI/engine hour. Anybody has such data?

 

[BVK]

Sorry - did not include truck data

Here is the truck description for the post Milage vs speed

 

[zari]

Well...

Isn't this really a pretty "moot" discussion ? Besides the obvious factor like GVW, other factors will greatly influence fuel economy. Don't know where I found these at, but they seem to correspond to what I've been seeing heuristically.



"Ambient temperature drop from 77F to 20F -> -5. 3% avg mpg"

"20mph head wind -> -2. 3% avg mpg"

"7% road grade -> -1. 9% avg mpg"

"27mph vs. 20mph stop and go driving pattern -> -10. 6% avg mpg"

"Aggressive vs. easy acceleration -> -11. 8% avg mpg"

"Tire pressure of 15psi vs. 26psi -> -3. 3% avg mpg"



Alain.

 

[AKsmoker]

I have 5700 on the truck and best tank was 18mpg running empty and 13 mpg with about 15k in tow. I'm real happy and expect mileage to improve past 10k. Got a buddy with the same truck and hes getting 14-15 mpg empty, both trucks are HOs. He has the Laramie and Ive got the SLT. Maybe its the $4,500 dollars in extras thats holding him back or more likely a lead foot!

 

[wxman]

At the risk of sounding like an "embellisher", I continue to be amazed at the fuel mileage I've obtained with my '03. I have ACTUALLY/HONESTLY achieved 21. 42 mpg calculated (8905. 4 miles on 415. 6 gallons of fuel). The mileage has gone up with time, and I'm getting nearly 23 mpg over the last 1500 miles or so. The truck is a 6-speed HO 4X4 with 3. 73, and weights 7220 pounds with me (~ 200 pounds) and a full tank of fuel, according to a certified truck scale.



I have not towed with this truck (yet) and generally drive the speed limits. I also ordered the truck with a tonneau cover which may help somewhat.

 

[E7mack96]

best mileage

Last weekend I did a run to michigan on sunday.



I was to take my time.



I drive at a religious 55 miles/hour for 267 miles.



I got 22. 9 mpgs.





This is the absolute best ever (I have never went that slow for so long before, lol)



Now, coming back, I poured the coals to her.



I went to 16. 3 MPGS for the return trip.



Weight was only 100, lbs difference (a Small High value load)



I guess the speed is the most critical part of the mileage quandry.

 

[bkaiser]

About 12K miles on the truck and speed makes a big difference. So far - Best mileage - PA to Maine and back, cap on, no camper - A/C on and cruise at 72 (2100 RPM) - 16. 75. 'Worst' mileage - PA to CT with 3100 pound camper and 4000 pound car trailer - A/C on and cruise at 69 - 11. 1. My old gasser got yards per gallon doing this job! It seems like it wants to run about 1900 in sixth to get the best mileage, but I can't go that slow.

 

[rossiride]

This isn't that tough to figure out guys!! It's RPM related, So yes 4. 10's at 75 is gonna be turning some r's. Everyone ones got a computer on the console. Watch it and try different RPM ranges, reset it and try another one on the same trip. Took me one trip to figure it out. Montana to Portland OR. 2200rpm(83 mph) @105 degrees (this is with 35" tires and 4 1/2" of lift, yes this is a sail) 16. 5mpg, same trip at 1800-1900 rpm's(70 mph), 19 mpg... ... ..... Figures show with stock tires and 4. 10's your turning over 2500 rpm's @ 80... . my 91 won't even turn that many r's and it get's 20+ easy at 75-80 mph just doesn't have as many ponies. What I'd like to know is if anybody with an air intake kit saw that rpm range move up higher? (thinking AFE pro guard 7 intake kit) I think it can't breath but haven't gotten anyone to confirm this yet! Let me know... ... thanks, Lee

want to know speeds and rpm's? check this out http://www.f-body.org/gears/

 

[JKibby]

I picked up my truck on 3-27-03 in Kellog, ID and drove home to So. CA. (you know the Socialist State. ) 95% Hwy miles 55 - 65 mph. 17. 9 mpg. Since then, I've been driving hard no towing 50/50 hwy/city avg. 14 mpg. I've taken one trip to Laughlin, NV. no towing at 75 mph 15. 9 mpg. Not really what I have been expecting to get for fuel mileage. I'm going to take a trip at 60 mph and see what happens.

 

[machinemover]

I did a round trip to Vegas today, 65 all the way there and 65-75 all the way back about 250 miles total. I'm lucky if I got 14 at best according to the on board computer. 3500,4x4 drw 4. 10 guess that's just what I have to live with. I'm waiting for the tst pack to come out and maybe that will help my mileage. It certainly helped my 2000 when I added it.

 

[MMeier]

Did a round trip from Vegas to Ely Nv. yesterday, 525 roundtrip just on board goodies about 9100 #'s 75 miles today, 50 with the race trailer to and from track. On the Ely run I averaged about 81 MPH and did two top speed runs of 115 MPH for a couple of miles each way and the low fuel light just came on at 591 miles! Are you guy's just going off the overhead or doing it on paper? By the way the EZ was on level 6 the whole time. Oo. The EGT's can get up there on the hi- speed runs though. Anyone elses turbo turning colors on the compressor side ?

 

[jman]

Best tank 20. 78 mpg. Usually between 19. 25 and 20. 25 with the trip computer showing 19. 8 right now. Drive 30 miles to work every day with about 18 being 55 mph, but I do have 4 stop signs to deal with and then about 7 miles of city driving. I don't drive like grandpa, but I don't drag race either.



BTW, My Intrepids overhead computer is within . 03 mpg compared to hand calculations. I would have never believed it if I hadn't done the math myself!!!

 

[rossiride]

I always double check mpg on paper, esp since the speedo is off with the 35" BFG's, and I'm always getting better then the computer says. It a good tool though to see when rpm's start sucking more fuel. Most of my towing is a 3500 lb boat and mpg runs about 15 with my foot in it big time and 17+ in town/hiway to work if I keep it under 2000 rpm's on the hiway with only a few races with BMW's in town.

 

[JKibby]

Originally posted by MMeier

Are you guy's just going off the overhead or doing it on paper? rolleyes:

Always on paper! The overhead is usually close +/- . 5 mpg but I don't use it much for mileage.

 

[SSage]

My mpg has been what I expected. I have the worst combination and a heavy foot. 15 mpg average, 18. 4 mpg best at 65 mph while empty. Loaded down with potting soil and rocks it will get 14. 8 mpg at 70 mph running two lane back roads with lots of red lights with 2500 to 3000 lbs in the bed.



No trailer pulling yet.



The overhead is lower than actual most of the time..... it reads 14 something right now, but I really got about 15 + mpg on my last trip of 230 miles with a load of large rocks.



This is the best running dually we've had. The Cummins is the best truck engine I've ever had. It gets the best mpgs of all our trucks which are 1/2 tons. My F-150 and 1500 Ram both get around 14 mpg empty on average with the big V8's. I don't miss the 360's 9 mpg while towing my rather light trailers (3 to 4K).