Gas milage killing me. Any suggestion to Improve

[green]

1500 av Z-71 with 4.10 gears. Still stock other than grille guard and F Keys. Averages 12.5 miles per gallon all around. Can get 15 while on hi way. Gas prices going up, love my truck but cost too much to drive. Any suggestions to improve fuel econ without messing up warranty? Is 12.5 a good average with this setup?

[RichUF]

my coworker with an '05 Z71 gets nearly 20 on his commute.

The 4.10 gears are not helping you I suspect.

The first, and possibly only non-negligible change would likely be from changing  how you drive.  Ease up some and see if it helps.

[ygmn]

do not smash gas pedal ...

Baby it..
drive like granny...

put brick under gas pedal...hehehe

[HuntOhio]

I am not sure about the gearing issue?  I get around 15 mpg city and around 20mpg on hwy.  This is with very easy driving without stomping at every light and using cruise control every chance I can.
Your mileage seems bad...I am looking into a inexpensive mod to change to a K&N air filter and maybe a new computer chip.  These can always be changed back and should not hurt the warranty.  Also it is fairly inexpensive to do.
My mechanic told me I should pick up 3 miles per gallon doing this.
Have you checked your tire pressure lately?

[RichUF]

...My mechanic told me I should pick up 3 miles per gallon doing this.
Have you checked your tire pressure lately?

Don't count on a 3mpg increase.

the tire pressure is a very good point, however.

[MS03 2500]

I agree with the K&N air filter I have a AEM Brute Force and I make a world of difference, I drive mainly on roads above 50 mph and it seems to be around 16-18 mpg. In stop and go traffic it not noticeable at all. I have the 2500 and I think thats good.

[green]

I do baby this ride. I drive 14 miles to work, takes about 25 min. I have even asked dealership if something was wrong? response it is within range.

[ygmn]

I do baby this ride. I drive 14 miles to work, takes about 25 min. I have even asked dealership if something was wrong? response it is within range.

well that is avg speed of 33.6 mph which is city driving....

so I bet lots of stop and go...which is when you will get crappy mpg...

[FlaBouy]

Tune, CAI, and exhaust mods will get you 2-3 mpg....Seen it a lot....the tune will be the best in the bunch... I was seeing 17-18 mpg on my 04 z-71 with the blower, 42# injectors and stock motor.... with stock injectors and a custom tune, 17 hwy should be easy....if you drive easy...

around town....fuggittaboutit......

[FAME2002]

When I accelerate in my avy, I keep the RPMS under 2000, its very slow to accelerate, but it really helps the gas mileage, the lower your rpms the less gas youre going to use, when getting on the highway or wherever you just have to accelerate as slow as possible. The people behind you will hate you....but theyre not paying for your gas!

[FlaBouy]

When I accelerate in my avy, I keep the RPMS under 2000, its very slow to accelerate, but it really helps the gas mileage, the lower your rpms the less gas youre going to use, when getting on the highway or wherever you just have to accelerate as slow as possible. The people behind you will hate you....but theyre not paying for your gas!

Good pointer......

Hehe....I am trying to remember the last time I could keep my rpm's below 2000......

hard to do with a 2600 stall....... of course I quit worrying about gas mileage a long time ago.......

[farmguy]

While there are a number of mods you can do that will marginally increase mpg, the most significant is change your driving habits. Use the cruise, slow down, easy on the gas, don't touch the brake unless you absolutely have to.

But the bottom line is don't buy an Avalanche for fuel economy. If that's your priority get a Civic or a Prius. If you want to enjoy the advantages of the AV, you gotta pay to play.

[DESERTAV]

I have a 65 in lift running 35 and I get about 15.5 city and 20 highway.  I changed my air filter to a K&N cold air induction and I am running a Hypertech power programmer.  Those 2 mods should help out a lot. Check the tire pressure it can kill your mpg

[FlaBouy]

I have a 65 in lift running 35 and I get about 15.5 city and 20 highway.  I changed my air filter to a K&N cold air induction and I am running a Hypertech power programmer.  Those 2 mods should help out a lot. Check the tire pressure it can kill your mpg

I would love to see that 65" lift..........

[RichUF]

what's your cruising speed over those 14 miles to work?  Interstate @ 70?

hate to say it, but 55-60 would help you out.

My 14 mile cruise to work in my '03 AV got me about 14 or 15.  About all I was using AV for 99% of the time, which is part of why I got rid of it

[MrJim]

Green,

I have a similar commute thru town - 12 miles (each way) and 18 (yes, 18!) traffic lights! A normal week will also see me put about  40-50 highway miles on he clock.  Normal weekly gas mileage is about 15 MPG .  Last month, my volunteer work took me out some country highways as well as the interstate and I got nearly 21 MPG.  My conclusions:

1. Our beloved AV is not optimized for city commuting.

2.  Big trucks with (relatively) big engines will not get stellar gas mileage, regardless.

3. Little cars with little engines will always get better gas mileage.

4. Little cars are easiled smushed by big trucks.

5. I don't want to get smushed.

It's kinda like death and taxes, except you do get some choice.


MrJim

[ygmn]

1. Our beloved AV is not optimized for city commuting.

2. Big trucks with (relatively) big engines will not get stellar gas mileage, regardless.

3. Little cars with little engines will always get better gas mileage.

4. Little cars are easiled smushed by big trucks.

5. I don't want to get smushed.

It's kinda like death and taxes, except you do get some choice.


MrJim

that was well put .....hehehe

[DESERTAV]

Sorry made a typo its a 6 in lift 

[green]

Ok, I am not a dumb A$$. I did not expect to get great MPG or I would have bought a small car. My last vehicle was a Chevy Crew 4X4 and it got close to 15.5 on the same commute. I would hope this one would be the same. AS for air pressure, I keep it serviced at the dealership. I wonder if the grille guard is affecting the dynamics. Does a K&M filter make a real difference, I saw the show on Dateline NBC that did not show any after market stuff helping any truck?
I have tried the 55 mph and it made no real difference in overall fuel economy on a tank of gas because I am only on the Hi way about 3 miles each way.
I love my slut but when gas gets to $4.00 per gallon love will fade fast, and we all know that $4.00 is not that far away.

[RichUF]

If I were doing what you describe and getting the mileage that you report, I'd take it back to the service department and complain some more.

[HuntOhio]

On a city commute I do not think the K&N filter would help you all that much.  A different computer chip may not help all that much either.  You may pick up 1MPG.
You would see the biggest difference on a hwy drive.
I also do not agree with all these guys that make mods to their exhaust and say they get all this extra power and killer gas milage.  These modern engines need the back pressure to run efficiently.

[FAME2002]

If I were doing what you describe and getting the mileage that you report, I'd take it back to the service department and complain some more.

I agree-
I can drive my 05 avy like a corvette, stomping on the gas, and I get 14-14.5mpg.  If youre getting 12-12.5 something is wrong.

[ygmn]

How are you figuring your MPG?

The computer thingy on dash?

or

Divide miles driven on tank by amount of full fuel fill??

[green]

I am using both the computer on the dash as well as fuel fill up to miles math.

[FlaBouy]

On a city commute I do not think the K&N filter would help you all that much.  A different computer chip may not help all that much either.  You may pick up 1MPG.
You would see the biggest difference on a hwy drive.
I also do not agree with all these guys that make mods to their exhaust and say they get all this extra power and killer gas milage.  These modern engines need the back pressure to run efficiently.

A-h-h-h-h a pessimist....would you believe actual log data from the HP Tuners datalogs that show increased airflow from certain mods including exhaust, CAI, power adders, etc... while driving in real world conditions, and not on a dyno...? Couple that with dyno charts to prove the power, and simple math to figure out gas consumption....

A good tune will increase your mpg from stock levels about 2-3mpg on the highway... Look up a posting on this site by a guy named farmtruc..... He is a professional tuner that also owns an AV..... he has tuned his own 2005 AV to get 19.1 mpg....

BTW with 19.1 mpg his bolt on mods get him the following at the track:

2.12 60'
8.99 1/8
79.77mph 1/8
13.93 1/4
97mph 1/4

Not bad for a inefficient 5800 lb truck in my opinion....  the ultimate "exhaust mod"............

BTW don't take my word for it........

http://www.chevyavalanchefanclub.com/cafcna/index.php/topic,63586.0.html