bad gas mileage

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

01Konvict

Boats n Hoes
Joined
Jan 16, 2011
Posts
2,734
Reaction score
682
Location
Raleigh/SML
My Yukon averages about 14 mpg in the city, usually around 14.5mpg but strictly city is 12mpg. Highway gets around 16-17mpg and all those numbers with 33s and mods in my sig.
 

xwt572

TYF Newbie
Joined
Jul 8, 2013
Posts
29
Reaction score
3
Location
Sweden
And for all the MPG´s... Do all of you have 4x4 or just 2wd???
No one with those fantastic numbers says what they are driving.
I´m in Sweden, and on the lower side, I drive a 4x4 XL.
 

jdpber

GOLD MEMBER
Supporting Member
Joined
Oct 18, 2010
Posts
26,314
Reaction score
24,310
Location
The America
2004 Tahoe 5.3 6" lift 35x11.5-20 3.73 4wd custom EFI live tunes. Flowmaster, airside cold air intake. I clean the TB once a month. Clean air filter every oil change, I run Lucas fuel treatment every other tank. Fully built transmission.

I milk it around town and I average 16 consistently on paper. And 18 hwy with hills, 20.5 hwy with no hills.

Now if I have heavy foot I see 10-12 in town.

Towing @ 65-70mph hill hwy a 5k 20' camper I get a consistent 10-11mgh the hills kill me.


Is this detailed enough information.

Dry no cargo hwy flat cruise set
70mph 1,825rpm
75mph 1,950
80mph 2,100

The taller tires help once I am in the 1:1 final drive ratio in the trans.
 

xwt572

TYF Newbie
Joined
Jul 8, 2013
Posts
29
Reaction score
3
Location
Sweden
Yeah, pretty much. I don´t want to step on toes, it´s just that many owners just have a 2wd. No wonder you will see higher MPG numbers. But yours seem pretty good.
Better than mine here in Europe.
The distances are shorter here as well. You guys are used to drive long distances without traffic lights, here it´s not uncommon to drive a 5-10 miles with a few roundabouts where you almost have to come to a stop. No straight roads for ten, twenty miles. There are of course, but less than "over there".
13 MPG when driving on E85, 16 on 95 octane (RON).
I see now that the US equivalent of the european 95 RON is 91 AKI.
When you fill up in the US, it says 87 or 91 octane, this is rated in AKI instead of the "european" style RON.
 

jdpber

GOLD MEMBER
Supporting Member
Joined
Oct 18, 2010
Posts
26,314
Reaction score
24,310
Location
The America
I never run E85 it's crap. I am tuned for 87 octane. The tune and driving ha bits makes the biggest difference in MPG. I roll start and slow go to 35 and at that point I can faster accelerate. I also have a computer monitor gauge that tells me any reading that the truck has a sensor for. So i look at the timing degree and the higher the timing the better the mpg. I balance that with the load aka throttle percentage based off of 100%. The monitor also has an efficiency meter that will beep if inefficient driving. Monitors acceleration and deceleration based on speed. And will give a grading based off of my desired mpg goals that I have programmed into the monitor. If wanting to maximize these vehicle you have to drive them right. Now I can afford to get 12 in town.

But I am not in a rush so I use city mpg as a challenge to me to try and maximize and find routes that yield a better output.

The key is your starts. If you hammer it you drink fuel. I have a calibrated unit based off of the raw hand calculated data over a 3month period of averages to have my monitor accurate. Not using DIC. And it has consistent accurate live numbers and it is scary if you punch it off line or even a 50% off line. How that will effect the overall tank MPG buy a consistent 3-4mpg a tank. Now if you think about it. Did punching it off the line actually get you to the destination faster? No. Same goes for speeding. Speeding only is efficient time saver if you are traveling long distances. Because in town you will be stopped at a light or stop sign or round about that will slow you and you will loose all gains of speeding. Now yes you me not get caught by the next light and beat the car behind you to the destination by 1-2 minutes at best but was it worth it?

I use the same thought when accelerating to the city speed limit. Does hammering it help you? I have found I take longer to get to the speed but I am still traveling with the flow if traffic. I have spent about a year testing these driving habit theory's. And slow roll off line to let the trans get you moving then work I to the acceleration yields the best overall tank MPG.

Off the line from a stop if you 50% throttle bump to 3k rpm you are getting about 3-5mpg at that acceleration. Give or take. And if you roll and gradual acceleration. You are 8-10mpg and if you do that eat every stop and go. You can gain multiple MPG per tank.

And with Europe fuel stations charging an arm and a leg and your first born for a full up. 2-4 mpg gain a tank will add up over the year.

Give it a try. And hand calculate. Also a clean TB and injectors along with balanced proper inflated tires. All the little things add up to yield a more efficient vehicle.
 

xwt572

TYF Newbie
Joined
Jul 8, 2013
Posts
29
Reaction score
3
Location
Sweden
Prices are steep here in Europe, that´s why I don´t use it for DD to work. More when we drive a little longer on holidays. I can´t really feel a difference when using E85, seems like it´s a little slower in response. Just changed the programming with a Diablo intune. Will see how that turns out mpg wise when we travel to the east of Sweden now at christmas and newyear, 200 mile trip one way.
In may we did that using E85, ended up with 13 mpg, all the way.
A few tools, 2 people, 5 cats, 2 dogs and the usual gear (100 lbs).
This time we will also take with us a double axle trailer (open), loaded with some furniture and other crap we need in the other house.
Trailer weighs in at 1100 lbs (no steamship carrier), load about 300-400 lbs.
Will be interesting to see what it does on the mpg.
Diablo intune has three programs to choose from, I used the first one, performer I think it was.
Seemed to be responding a little better on E85, but that can be "wishfull thinking".
 

jdpber

GOLD MEMBER
Supporting Member
Joined
Oct 18, 2010
Posts
26,314
Reaction score
24,310
Location
The America
What is the cost difference between the e85 and regular. For me it is worse on mpg and mathematically to cost cost more to run it. Not many of us in US use it bc it is CRAP

I would try running a regular gas for one leg. And the other for the return. And compare. Try to roll starts. And a slower acceleration to final speed. And see how that does for your mpg. Remember these ECM are learning and will change fuel mapping as to driving style and how they are reading the TB air flow. And other readings which all can effect mpg. But I'm wiling to bet if you ditch the E86 and run real gas and a slower acceleration with less hammer to the throttle you will gain.
 

xwt572

TYF Newbie
Joined
Jul 8, 2013
Posts
29
Reaction score
3
Location
Sweden
95 RON = 7.78 USD per gallon (US).
E85 = 5.64 USD per gallon (US).
13-16 MPG.
 

Grimes

Full Access Member
Joined
Apr 13, 2013
Posts
413
Reaction score
4
95 RON = 7.78 USD per gallon (US).
E85 = 5.64 USD per gallon (US).
13-16 MPG.

I love central Texas because my 87 is $3.02.

Also, just to throw it in. 5.3L 2WD before tune I see:

Life meter of 206k said 15

Personal meter after 1k, mostly city, after CAI and exhaust said 15.3

Meter after a tune and on 89 octane said 18 highway, and about 16 city. Once I am used to the tune, and I grow up a little inside and keep my foot squared away, I'm sure those numbers will only rise.
 

Forum statistics

Threads
129,270
Posts
1,813,078
Members
92,378
Latest member
Luggz
Top