Just got a 2005 H2 and MPG is really good
 

At least in my opinion. All I ever heard were horror stories of 10 and 11 mpg. But I've been averaging 14+ mpg for the last 2 months. Even the guy I bought it off of thought I was crazy for buying before I took a trip to Utah, Vegas, and Havasu. It averaged a little over 16 MPG. I tuned it with HP tuners and installed an intake. I just installed a cat back. I was hoping for even a little better mpg. And this is a 2005 H2 with air suspension and 20" rims.

What have you been smoking?

Ain't been smoking anything. Smoking is kind of nasty.
Mpg went down to 13.4 After some brutal traffic this week. But after driving this weekend, it slowly climbed back up to 13.9.
I reset the average economy every fill up.
And this is us gallons here in new mexico.
Considering how comfortable this h2 is, I think the 13 or so mpg is so worth it. My jeep gets about the same mpg but it's like half the size.

Real 16 mpg with a H2 in every day driving is not possible.
I did 15.2 at best one day going 55mph behind a large trailer for 2 hours on the interstate, but that is not normal day to day driving.
Normal intersta driving 65-70 you can get about 13 but with mixed city/higway driving you will get 10-11mpg
Also did you rely on the mpg in the dash or did you divide driven miles by gallon pumped?

What year is the H2? I believe the 08 & 09 had a 6 speed auto vs the 03-07s which had a 4 speed auto. What size tires do you have on those 20" rims? That could be throwing off the computer.

The only way to get "true" MPG is to fill up, reset the odometer, drive, fill up get the miles driven and divide miles driven by gallons used. If your tire height is different from the OEM size (315/70R17 or 35") you will also have to calculate for that difference and modify your math accordingly.

I truly hope you are getting the MPG you stated.

Mark he has an 05 and I think you hit the nail on the head. I think his tire/wheel combination is throwing his mileage computer off.

Even when my truck was bone stock it never got anywhere close to 16mpg...:rolleyes:

I calculate my gas mileage on every fill up. I top off the tank every time. My speedo is accurate. I verified it on my awd dyno. The tires appear to be stock diameter tires as I didn't have to make any gear ratio changes in the tune.
It is very amusing how strongly certain people want to argue that this isn't possible. 14 Mpg isn't exactly something to boast about. It's a small improvement that should be realistic based upon the characteristics of the H2. Me and my wife both drive the H2. So it's not like I'm doing something crazy with my driving habits.
I really didn't see any improvements in the mpg with the exhaust. But I do like the sound at least. And there's some exhaust tips that stick out the back.

Just having put a lot of miles on two H2s ( 03 and 05 ) the best I ever did was about 14 mpg on an all highway trip with a tailwind. Average mileage over 50,000 miles was 10.4 and I was trying to milk it as much as possible. Around town my average was more like 8 mpg. One of my H2s was totally stock on 35" BFG AT tires and one was on 37" Toyo Open Country tires. Just speaking from personal experience. Having been a moderator on numerous Hummer forums for the last 6-7 years I have heard a lot of mileage statistics on these trucks and yours are outside the normal range by a good bit.

you guise are all jealous.