I got a 2006 H3 with 176k Km's. Gets around 400km per tank. ITs winter right now where i live(saskatchewan,canada) so we warm it up before we take it out. Just wondering what everyone else gets in there hummer!

 

You're on your own to convert to metric. I get between 13.5 and 14.5mpg.

Here's a couple threads that touch on either what people are getting for fuel efficiency, or thoughts on how to improve it:

https://www.hummerforums.com/forum/h...mmer-h3-28145/

https://www.hummerforums.com/forum/h...mileage-27548/

https://www.hummerforums.com/forum/h...age-mpg-28707/

https://www.hummerforums.com/forum/h...ter-mpg-28662/

https://www.hummerforums.com/forum/h...mileage-19406/

https://www.hummerforums.com/forum/h...mileage-30150/

https://www.hummerforums.com/forum/h...mmer-h3-30068/

 

Also, What fuel do you use? We put in premium , always have since we got a major service done on the hummer a while ago(fluids,filters,etc)

 

I get 12 with lots of extra weight, and 34.5 inch tires

 

I always have my rig loaded with tools and do all city driving...still avg 14mpg. I only use premium.

Just as it was advertised:

Fuel Economy of the 2007 Hummer H3 4WD

 

I get no more than 420 kms and no less than 380 kms off a tank in alberta. A tuneup to your Hummer does not warrant premium fuel. Ive tested fuel multiple times. Premium vs regular ive had NO difference in fuel economy and NO difference in power.
I have a 06 h3. 120k on body. 15k on new crate engine. With 285/75/16 tires.
Premium fuel is usually recomended for high compression engines which the 3 has.. But I have yet to see a difference.

 

I know it may not do anything. But I'd rather put fuel in thats better and has no ethanol, for 5 -8 bucks more a tank. and i can afford it. so why not

 

Just purchased a 2008 Alpha with 33" tires. First tank only got 10mpg of city driving. Ran a can of Seafoam through it and went to 97 octane. Interstate road trip over the Rockies was an amazing 19.5 mpg. Next trip into the Rockies and a few hours of breaking snow drifts and moderate hill climbing 14.5 mpg. Couldn't be happier with my v-8.

 

I live in new Brunswick. I got about 500-600km with mixed city and highway driving when i got it. i put heavier tires on and get a bit less but not that noticeable. I only run regular. Also i just cleaned my tb and maf yesterday and seems to run smother and have a.bit better response. Tb ws filthy. i figured roughly 16-18 mpg

 

Hummerz it does not call for premium gasoline. Just regular. That link you posted calls for regular also. I honestly don't know if putting a higher octane would gain any mpg or not. Maybe slightly. I don't think it really would be enough to make up for the cost of the premium gas though. And the horsepower? possibly a little higher, but I would think over the long run the premium is just going to cost more and not do much for your H3. Get a pcm tune, a one time cost and gain some hp's and mpg there. H3's call for 87 octane fuel. We run a tank of premium through periodically but we use 87 like it calls for everyday driving.