14.5 Average.
I have the K&N CAI and SMA dual exhaust. Average speed on hwy 65-73MPH.
24 miles to work(one way), most is fwy time.
89 octane.
16700 miles.

Is there a difference in the gas mileage between the 32 and 33 inch tires ?

I've keep track of fuel used since day one and have averaged 15.3 mpg during the last 12,500 miles. That includes 1000 miles of four wheeling with the rest being a mix of 50 / 50 street and highway. Oh yea...... I might exceed the speed limit from time to time and live in Phoenix so the A/C is on all the time.

My vehicle has the following options which may effect MPG:
Off Road Package, Auto, Roof Rails and I have raised the front about an inch.

How do you figure out the milage? The computer does not give that?

Thought I would add high and low.

High 100% highway 20.6
Low mostly in town 13.7

Low 8.7 (all off road)

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by WPBGUY:
How do you figure out the milage? The computer does not give that? </div></BLOCKQUOTE>

Well, for me I'll fill up the tank and set one of the trip odometers to zero. Drive until the "low fuel" light comes on. After I fill her up, I'll look at my mileage and calculate my MPG. Total miles driven/gallons put into the tank.

5300 miles, Mobil 1 synthetic, 265 base tire at 35#. Flat and at speed limit..20.1 Hwy, 15.5 city.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by WPBGUY:
How do you figure out the milage? The computer does not give that? </div></BLOCKQUOTE>

Keep track of how much fuel you have put into the tank and then use the trip odometer to see how many miles you got out of that fill-up. It’s a little hard to be completely accurate, but here’s one method that is pretty close:

1. Go to a gas station, pick a pump.
2. Fill it up until the pump clicks off.
3. Reset the trip odometer to zero.
4. Have some fun
5. Go back to the exact same pump under similar conditions (~ same time of day, same outside temperature), fuel up again until it clicks off
6. Record the amount of fuel and record the miles on the trip odometer.
7. Do the math

My gas mileage under my "driving" habits = 13.5 mpg.

Ouch, that really hurts.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by ketcat:
Thought I would add high and low.

High 100% highway 20.6
Low mostly in town 13.7

Low 8.7 (all off road) </div></BLOCKQUOTE>
hey ket good #'s are you running a hi psi ? I run mine on highway at 38-40 psi . got 21.4 coming back on 150 mile run 62mph -65mph just cruisen averaging 17 in town . tire rating is 50 psi [on sidewall] so before everyone slams hi psi's , tires will wear even . 38-40 psi will ride stiffer and a little more floaty over 75 mph , but if your commuting like i do and dont mind cruisen 65 its worth an extra 5 mpg and mine is an automatic . i have over 6k in miles now so well broken in also . I havent computed my offroad at 20 psi yet

NEOCON, if your getting over 21, Im going to adjust my pressure as well and try it. I also commute and could use the extra mileage. 10,000 miles and going strong.

12 mpg for me. mostly city driving. also have true-flow air filter.

We have 2 H3's. My wife's is yellow and mine is black. She's had hers 4 months (6000 miles) and said her best mileage was 22 and her worst was 16. Mine is 2 months old and only has 1400 miles on it (I split the driving between my CJ7 and the Hummer to keep the mileage down). I get 17 most of the time. We comute to Tulsa from the country about 33 miles one way so most of our driving is highway. I did the "torsion bar crank" thing on mine to gain 1 1/2" of lift in the front. I'm leaving hers alone until I see how it works out. Love those H3's.

man o man.....
i get about 200 miles from top off to low fuel light.
i have 35" superswampers on...
i knew my mileage was bad, but didnt think it was that bad.
now i know.

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by 818Guy:


My gas mileage under my "driving" habits = 13.5 mpg.

Ouch, that really hurts. </div></BLOCKQUOTE>

I've got just over 7000 miles now, have checked mileage on every fillup. Low has been just under 16, high has been 18. Mine is auto with adventure package.

I haven't done any offroading, my driving is probably about what you do, 70%HW/30%City. I drive a bit faster (73-75) on the highway (this is Texas after all).

I don't know how yours could be so bad. It does sound like there is quite a bit of variance among the people here. If this is going to be a primary decision criteria for you, the H3 may not be the right vehicle. You'll beat yourself up every time you fill up.

Me, I just have fun driving it and keep investing in the energy companies.

Good luck!

HumbleAg,

That is what is killing me so much. The gas mileage. If it was around 15-16, the H3 would be in the mix for my next vehicle. Granted, I wish I would have checked the tire pressure before my "test."

The H3 is still in the running but fuel economy is one of the things I'm considering.

BTW, I live in Los Angeles.

Side note, when I was at the Hummer dealership the salesman said that a CAI and exhaust "will" improve mileage.

Any truth?

I have almost 4K on mine and lately have 15.5 stop and go and 17.5 highway. It gets better with time, as I was averaging 13.5 and 16 before.

My current car, 2004 Mazda RX-8, had the similar situation. I was getting about 13 mpg mixed driving for the first 15k miles. Since then it's up to about 18 mixed. Currently I have 21000 miles on the car.

But that's where the H3 comes in. If I'm going to get 17-18 mpg with mixed driving, I might as well be driving an SUV just for the utility and room of it.

I'm getting around 21 mpg. with the base, 5 speed manual