How to improve MPG... [Archive] - Hummer H2 Forum: H2 forums

How to improve MPG...

12-02-2009, 03:15 PM
A full size Suburban get lots better MPG (18-21) with the same engine/trany and weighs more, why do the H2's get such bad MPG? AWD vs 4x2 on a 4x4 suburban... or ????

I am compiling a list of things that can help the MPG. These are things known to work, not advertisements.

Please add to this list anything you have done to help improve your MPG.

These are things beyond normal driving tips like tire pressure, regular maintenance, reducing weight, removing rear luggage rack or not having anything hanging on top of or out of the H2 to driving slower.

Here is what I have so far:
1) Change to a free flow air cleaner, cold air intake, K&N or equivalent.
2) Change to all synthetic oils in all running gear.
3) Free flow exhaust, Cat back to Cat replacement and full exhaust.
4) Headers, with full free flow exhaust to include a free flow cat..
5) Replace mechanical fan with Electric Fan.
6) Super Charger
7) Engine (programmerís) turner, if you know how to do it.
8) E-3 spark plugs. (

Things not tried, don't think they work:
1) Magnetic fuel savers
2) Intake vortex generators (I did try this in my Dodge Diesel and a Jeep Liberty, NO help at all.
3) Hydrogen generators
4) Air tabs or spoilers

I am not trying to get my H2 to match my Honda for MPG, but I just don't think I need to waste any either.

What have you done?


Mistriu fase
08-16-2014, 02:25 AM
If you struggle hard for it always it get Higher MPG than the Honda because Honda engine has a lower MPG value set but H2 is of high performance so because of this it get higher MPG,its not a fault.