REAL World MPG's

THE-BEAST

New member
Jan 18, 2009
44
0
0
........

BTW truck has 3,000 miles on it. I dont really see fuel mileage getting much better?.



That rig is no where near broken in........ I didn't see MPG gains I could attribute to break-in until over 30K....... Get 19 MPG most trips running empty now......... Sometimes 18, sometimes 20, heck I even got 21 on a tank in ideal 60 MPH conditions at sea level.

Most trips towing 6K see 12 MPG. But then I don't push it to 70 MPH towing. Have to be able to stop the load too! ;)

Just did my 2nd fuel filter change thru the access panel I bought off eBay.

We'll see if that new coelescer filter makes any dif.


:coolspot:
 
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lotsofmiles

Father of the Van
Dec 4, 2008
3,097
0
0
Michigan
I'm confused.


I am extremely efi challenged. but it looks to me if I log it at 70 in 6th and then manually drop it into 5th that fuel consumption goes up as does the rpms.

So if fuel consumption goes up and the motor is spinning at 300 or more rpms how is it that 6th gear doesnt do anything for mpg's?

not trying to be difficult, just trying to learn.:hug:
 

WolfLMM

Making Chips
Nov 21, 2006
4,005
25
48
38
AL
That rig is no where near broken in........ I didn't see MPG gains I could attribute to break-in until over 30K....... Get 19 MPG most trips running empty now......... Sometimes 18, sometimes 20, heck I even got 21 on a tank in ideal 60 MPH conditions at sea level.

Most trips towing 6K see 12 MPG. But then I don't push it to 70 MPH towing. Have to be able to stop the load too! ;)

Just did my 2nd fuel filter change thru the access panel I bought off eBay.

We'll see if that new coelescer filter makes any dif.


:coolspot:

My truck gets 18 unloaded.... This boat must catch some serious wind.
 

Turbotug

BEER SLAYER
Sep 3, 2006
1,019
1
38
46
Phoenix
I used to log every tank, got 20+ calculated by hand..

Easily gets double digits towing my loaded toy hauler..

truckntrailer-1.jpg
 

Cornell

LBZ for life
Sep 11, 2006
1,601
0
0
Minnesota
I get 17.5-18 in town unloaded. If I'm on the highway it goes up to 20 if I keep it around 70-75

Pulling our T300 bobcat with forks and a bucket is around 14k and I get 13-13.5
 

Duracopter

<-LBZ Project
Oct 29, 2009
50
0
0
Little Rock, AR
My LLY got 14.5mpg on a trip to Missouri from Arkansas, this was with 10K load and running mixed speeds rangeing from 50 to 80mph, It also gets 21mpg empty. So that is some low milage, LOL that boat must be a ship!
 

bpe

New member
Jan 8, 2010
2
0
0
I get 7.9 pulling my rv. It is a big wind drag though. Larger tires than stock also hurt pulling this much weight. Effectively raises rear gear ratio so motor has to work harder. I lost 2 mpg with taller tires and will be going back to stock height when these wear out.
 

WanaDmaxsub

Junior Member W/gray hair
Feb 17, 2007
644
1
18
315-70/17 Tires
Towing a 7K TT
A low of 9mpg and a high of 12 (12.1...once....)
The average is in the low 10's.
 

JMDuramaxLB7

YOU SAID MEMBER!!!
Jun 3, 2007
744
0
0
Missouri
I get 20+ all the time in the summer and 12 to 13.5 towing 25 ft. gooseneck with antique deeres with total weight around 20k. Right now, winter time i'm getting around 14 to 16 empty with alot of idle time also. Its been said before and i'll say it again, LB7's are the kings of mileage when your talking duramax's...
 

2004ChevyDmax

New member
Dec 19, 2009
21
0
0
That does suck. I got a '04 with the LB7 and I pulled an older Powerstroke about 350 miles, and I think I was getting around 15 mpg at around 70 mpg in Tow/Haul mode. It was all pratically interstates. I think I even got about 17 mpg with the empty trailer. The truck is completely stock. My mileage has dropped off some now, but I am fairlycertain that my filter needs changed and the winter has set in too.
 

johnasara

EFI'ed
Jun 5, 2009
20
0
0
Middle of nowhere, NM
I got 7.5 out of my LMM once pulling a bobcat at 75mph. It averages around 11.5 now towing my 10k trailer. The truck also weighs 11k "empty" ohh and the DPF fell off about 20k ago
 

NemesisDP

New member
Apr 20, 2008
520
0
0
Bloomfield New Mexico
I get around 12-13 with my LBZ pullng 18-20k on a flat bed trailer with low wind resistance.

I get 8-10 towing a 30ft camper at 65, if I run 75 I get around 6-8 mpg.

I have 285/70/17's I think. 285/?/17's run 5th and 6th gear depending on exhaust temps
 

Rikter

Grumpy, old, farty, funny
Jan 14, 2010
61
0
6
Calgary
Avg MPG Towing thru Mtns

I towed a trailer with a loaded truck, trailer & buddy combined weight of 17,878lbs. My average mpg was 15mpg. That includes mountain driving to an elevation of 3800ft at an average speed of 63mph over 200miles. We had 2 quads on the trucks sled deck & they stick up & give some air drag.
 

mead

New member
Feb 12, 2009
32
0
0
san diego
just did 3,000 with 23'tt about 5500lbs
towed in 5th, avg 11mpg. at 70 to, 75 mph.
avg egt 900 to 1000 max about 1200
same trip last year avg. 7 in stock form.