RE: Horrible gas mileage any reason?

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RE: Horrible gas mileage any reason?

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RE: Horrible gas mileage any reason? - 7/11/2007 7:50:06 AM

Dennis

Posts: 7584
Status: offline

quote:

ORIGINAL: Shannon

Remember....I am the dumb blonde that knows nothing about cars, but I am trying to learn since I am so excited about the new Hummer.....female oh, course....

Oh cool..So flirting will be okay then?....I like dumb blondes

< Message edited by Dennis -- 7/11/2007 7:51:36 AM >

(in reply to Shannon)

Post #: 31

RE: Horrible gas mileage any reason? - 7/11/2007 8:53:49 AM

tmoody

Posts: 69
Joined: 7/10/2007
Status: offline

just went through the first tank last night. calculating from the fill up, I averaged 17.8 mpg keeping it "mostly" under 55mph.....certainly under 65mph.

(in reply to Dennis)

Post #: 32

RE: Horrible gas mileage any reason? - 7/11/2007 8:55:38 AM

HummerGuy

Posts: 6684
Status: offline

quote:

ORIGINAL: Dennis

quote:

ORIGINAL: Shannon

Remember....I am the dumb blonde that knows nothing about cars, but I am trying to learn since I am so excited about the new Hummer.....female oh, course....

Oh cool..So flirting will be okay then?....I like dumb blondes

< Message edited by Dennis -- 7/11/2007 9:51:36 AM >

OK Now you are just doing it intentionally to annoy me

< Message edited by HummerGuy -- 7/11/2007 9:04:34 AM >

(in reply to Dennis)

Post #: 33

RE: Horrible gas mileage any reason? - 7/11/2007 9:16:16 AM

HummerGuy

Posts: 6684
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quote:

ORIGINAL: tmoody

just went through the first tank last night. calculating from the fill up, I averaged 17.8 mpg keeping it "mostly" under 55mph.....certainly under 65mph.

If you search through our bazillions of MPG posts, it looks like MOST people on this forum average between 15 to 18 MPG going between highway and city, regardless if the AC is on and off. On those RARE 75 degree days when you don't need AC and there is NO wind and you are driving 60 on the highway, some of us have gotten 20 to 22, but that is RARE.

(in reply to tmoody)

Post #: 34

RE: Horrible gas mileage any reason? - 7/11/2007 4:33:17 PM

hummernewby

Posts: 241
Status: offline

I'm not doing that great on mine, its mainly city driving and average around 14 mpg. I make sure not to do the jack rabbit starts or hard braking but I guess like everyone says it just needs to break in some more.

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Post #: 35

RE: Horrible gas mileage any reason? - 7/18/2007 10:18:34 AM

pmalla5

Posts: 162
Joined: 6/7/2007
Status: offline

my h2 was normaly at 11.3-12.5 which was like amazing but after i installed CAI im gettin 15 and on a good day max 17 never more

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Post #: 36

RE: Horrible gas mileage any reason? - 7/18/2007 12:36:59 PM

samvoiceman

Posts: 67
Joined: 7/16/2007
Status: offline

tire pressure cold at 39 psi really helps!

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Post #: 37

RE: Horrible gas mileage any reason? - 7/18/2007 4:08:59 PM

PSYCHO

Posts: 28
Joined: 7/8/2007
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OK, only have two tanks used so far, 1st tank (city/highway 30%/70%) was 15.06 MPG, and the 2nd tank, (100% city) 12.45 MPG.
Hope to improve after installing Cat back system and CAI next week, (if I get the parts)!

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Post #: 38

RE: Horrible gas mileage any reason? - 7/18/2007 4:25:39 PM

Dennis

Posts: 7584
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You will and it should be broke in at about 6000 to 8000 miles..which will make a little difference too.

And if you change your oil to a synthetic ..

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Post #: 39

RE: Horrible gas mileage any reason? - 7/18/2007 10:05:15 PM

novasaigo

Posts: 157
Joined: 2/24/2007
Status: offline

My gas mileage averages at about 19 on the hiway. I keep my factory goodyears at 40psi instead of the 30 that they recommend. That could have something to do with it.

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Post #: 40

RE: Horrible gas mileage any reason? - 7/18/2007 11:22:55 PM

vince1128

Posts: 2
Joined: 7/18/2007
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Does the PCM void the warranty. for that matter does a CAI or exhaust?
sorry if these are "noob" questions

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Post #: 41

RE: Horrible gas mileage any reason? - 7/19/2007 4:16:57 AM

D VADER

Posts: 1191
Joined: 5/21/2007
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quote:

ORIGINAL: vince1128

Does the PCM void the warranty. for that matter does a CAI or exhaust?
sorry if these are "noob" questions

GM has a disclaimer in place that says anything that adds horsepower or torque will void your drivetrain warranty. With that said, very few Service Managers will hold you to that with a CAI and exhaust change...but technically they can. I had a talk with my salesman and Service Manager about those mods when I bought the H3 so I shouldn't have a problem. They even told me they would install them, which adds a bit of confidence.

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Post #: 42

RE: Horrible gas mileage any reason? - 7/19/2007 5:46:46 AM

hummah

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Joined: 6/22/2007
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I have an '07 that when it is driven on the highway at speeds between 60 and 65mph the mileage I get is 21mpg. Anything over 65 and the mileage plummets. Overall between highway and city driving the vehicle averages about 19. Hope this helps

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Post #: 43

RE: Horrible gas mileage any reason? - 7/19/2007 5:59:24 AM

Dennis

Posts: 7584
Status: offline

quote:

ORIGINAL: D VADER

quote:

ORIGINAL: vince1128

Does the PCM void the warranty. for that matter does a CAI or exhaust?
sorry if these are "noob" questions

GM has a disclaimer in place that says anything that adds horsepower or torque will void your drivetrain warranty. With that said, very few Service Managers will hold you to that with a CAI and exhaust change...but technically they can. I had a talk with my salesman and Service Manager about those mods when I bought the H3 so I shouldn't have a problem. They even told me they would install them, which adds a bit of confidence.

I don't want go this route again with you again Bob...but I believe this to be total BS and I hope you stop putting that out there..I have not seen it, nor does my service manager here in OKC or Little Rock ever seen such a disclaimer...In any event, the Magnuson Moss Act will dispel that disclaimer anyway...Every dealer here in the SW that I know of, are doing aftermarket or OEM mods for performance enhancement to the H3s...I know personally the PCM tuning as is being done by Lund Cadillac/Hummer of Phoenix.. and Albuquerque's Hummer Dealer.

So to answer your question Vince..NO!...you will not void any warranty with a PCM tune, or a CAI, or Cat-back exhaust..So go forth and improve your H3's performance without worry...I'd be more concerned about lift kits that put a stretch on the CV joints.

(in reply to D VADER)

Post #: 44

RE: Horrible gas mileage any reason? - 7/19/2007 7:08:47 AM

D VADER

Posts: 1191
Joined: 5/21/2007
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quote:

ORIGINAL: hummah

I have an '07 that when it is driven on the highway at speeds between 60 and 65mph the mileage I get is 21mpg. Anything over 65 and the mileage plummets. Overall between highway and city driving the vehicle averages about 19. Hope this helps

On a 1500 mile trip to Savannah GA the best I could do was 16mpg. That did include mountain driving and often at 80 mph.

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