Well not really but recently installed the scangaugeII and while cruising down the local road at 1600~1800 rpm going about 30~35 mph scangauge shows 23.5 +\- mpg and was wondering if the car was really doing that much.

 

At that pariticular moment it likely was. Watch the gauge and see what it says next time you pull away from a stoplight or going up a hill. It all evens out to being moderately crappy.

 

LOL, 18mpg from an SUV isn't crappy at all, unless it's the 5.3l, then I would imagine it is slightly worse.

 

Most trip computers that also calculate mpg are off by a couple mpg.
You can do a simple test tho
Next fill up, fill tank to top of neck and then zero trip computer and then do the math on the next fill up. Of course, now you have to believe the odometer, but you have nothing else.

Do not trust the auto shut off, they can be very sensitive and shut off with as much as two gallons to go. A friend who works for Chevron in Richmond CA checked the Healy shut off's around the west coast area and found them to be overly sensitive.

I have an 07 H3 and the adventure package and the best mileage I have ever gotten is 21.5 mpg on level highway (sea level) and driving about 60 mph

 

Just to put in
I have an 06 H3 and when we travel the highway and keep it around the 55-60 mph we average 22-24 mpg so it is possible.
When you start driving the rig hard and start and stop quickly the mpg drops.

 

It seems crappy considering I have 2 other vehicles in the garage that get 36 and 38 mpg.

 

Yeh well my work truck is an 07 dodge 1500 5.7 and that hemi drinks gas in comparision to the H3, we leave for a trip to the mountains and going to travel 2000 miles or so and I am going o track it again to make sure, I also put in the fuel system treatment every 2nd tank and every third I am going to put in a jug of seafoam. See how that will work out.

 

Obviously you are a hippie.

 

Maybe he has a couple of motorcycles in the garage. But still, might have to check yourself for birkenstocks anyway!

I get 12.0 mpg on surface streets and 17.5-18.0 on the hwy at 70. Might just have to get a cycle to even out my carbon footprint but my old KZ1000 would get 24mpg or less from stoplight to stoplight. Lol

 

Funny, I don't feel hippie-ish??

My point is the H3 with the 5 cyl. engine that is what I would consider sufficient for most situations, but not having surplus power, gets much worse gas milage than many trucks and SUV's that have tons-o-power. Heck the H3 Alpha only gets a couple mpg worse in stock configuration and can be massaged to get equal milage without much investment.
A motor such as the Ford Eco-boost V-6 puts it to shame with 350 hp. Heck, the I4 Ecoboost puts out the same 240 hp as the GM I5 with more torque (270) and gets 28 mpg on the highway. So 18mpg is indeed somewhat crappy in today's world of motors. Granted the I5 is now somewhat outdated as well.