I have a new 2006 H3 (leftover). I love the truck and it drives great. The gas milage is way off from the EPA estimates (19 highway, 16 local). My first full tank of gas only gave me over 250 miles to close to empty (slightly over 10 MPG!). My driving is local with some highway. Has anyone else noticed this? The vehicle was not built to "cut the air" and conserve fuel, but this does seem to be real low. Hummer suggests to keep the tire pressure at 30 PSI but the tires are built for a max of 44 PSI. HAs anyone tried to up the tire pressure if your primary driving is on the road to help address this issue? Has anyone successfully installed a throttle body spacer and seen any inprovements?

Thank you.

PLEASE "TREEHUGGERS" AND OTHER CAR LOVERS (foreign or domestic) - I DO NOT CARE ABOUT YOUR OPINION ABOUT HOW THE HUMMER IS THE MODEL OF AMERICAN WASTE. I SERVED IN THE USMC AND YOUR RIGHT FOR AN OPINION. FELL FREE TO HAVE YOUR OPINION, THAT IS WHAT WE SERVED FOR. Please start a new post if you are on this site to post your views. I am curious about hearing from actual H3 owners only.

Semper fi.

 

It sounds like you may have developed a lead foot. I have noticed that more sensitive and economical driving will get you 15 or 16 in town and 18 or 19 on the hwy. I think some folks tend to push that little 5 cylinder too hard when the reality that iti is not a V8 sinks in. It is a great truck but is definatley not built for speed or quick take offs.

In mine if I have a heavy foot then the mileage goes way down.

GH

 

or you have got the one made right after mine cause I was getting around 10 -11 mpg stock. Now with 35's an an intake I get 8.5.

And don't worry, you will only hear from actual hummer owners here...we are a hummer only forum and police the scum out rather quickly

 

Im get high 14s out of mine. I think between lifting the frount and putting on the rack
its draging me down. But Its FUN

 

Yeah man I hate to say it but you're not gonna ever get 20, unless you change the aerodynamic properties of your H3 to be more like those of the Concorde. In the city you're lucky if you get 14.

I've really noticed that taking it easy on the throttle makes a big difference. I've got comfy leather seats and nearly infinite musical choices to sample & bide my time in while I get up to 65 mph.

I've noticed that's where the I-5 is comfortable on the highway (65-70 MPH). Cruise control really helps you maximize the MPGs as well. I barely got 17 MPG on a 6 hour road trip back to Mississippi. But hey, it's a hummer; it ain't built for speed or fuel efficiency.

 

I get 18 on extended highway trips driving nice and about 65. See my signature for mods. The throttle body spacer on the dyno for Colorado's made 10hp 6 ft lbs and 2-3 mpg on road test. Since we have 4wd full time cant dyno around here. My actual did go up but all together with the plate, intake and no muff really made for overall peppy perfomance. Raises the front end when you nail it on the on ramps. Growls crawling up rocky hills. Humms a little at 65. Just crank up the Monsoon!! It passed the wifey test! Now for my PCM........Roll your windows up fold back the mirrors and keep your hands, arms and head in the vehicle. Oh I do run the sunroof open but dont care what that does!

 

I have no plans of testing my gas mileage out ever that's not what I bought it for But I can tell you I have never gotten 300 miles on a full tank before and I drive very responsibly it's just not something I worry about. One thing that always makes me feel better when paying a large gas bill I know won't get me as far as I would like is to think....oh yeah I have a hummer.

 

I got pretty poor gas mi. on mine at first as well. (But, I didn't care! I was driving a Hummer! AND, my previous Jeep GC was no great shakes in the gas mi dept either.) I never really checked the GM carefully in the beginning - I just knew a tank went in a real hurry! I found that with each new full tank, more mileage, and more engine break-in, I was getting better and better each time. I am now up to approx 17+ HWY (speeds of 75-85 mph) and 15-16 city. I do not have a lead foot unless I am on the interstate, and I drive relatively "politely." I've had her 6 mos and about 7K miles now. Perhaps as you break her in, she will do better as well.

LOVIN MY LITTLE HUMMER! [sm=smiley27.gif]

 

Thanks guys and girls. I do agree... it is a hummer. If I wanted the savings on gas, I would not enjoy driving the H3 everyday.

BTW. The one post I read had a bunch of Toyota/Honda people reading which makes no sense.

 

My wife gets 14-15 around town all the time. On road trips it has varied, and most of the road trips were into the hill country (a lot of steep hills to pull).. but we've usually gotten 16-17.xx (75/80 mph). So I'm not complaining. That's better than our Tahoe got.