I just recently bought a 2007 H3x and I love it. The vehicle had 13000 miles and was in perfect condition. I have did some looking around the site and reading up on threads. I'm sure this has been mentioned somewhere but I couldn't find exactly what I was looking for. I am getting ready to put 33x12.50/18 on the hummer and am looking for ways to improve my mileage a little bit.

I'm aware that I bought a brick on wheels, and do not expect 20 mpg, but a few extra miles would be nice. I am thinking about a cold air intake, and a throttle body spacer. Has anyone tried this combination? If so, what were the results? Any other options?

 

nevermind on the spacer. Seems that everyone here agrees that they are junk. I'll decide on a intake and just go with that.

 

Go for a PCMtuneforless to. I have heard of 3mpg gains. It's on my list of have to's.

 

i would go there and read their claims/disclaimers

if anything would give 3 mpg gain it would be worth appx $350 the first year if
i drive 12000 at 16mpg at 3 bucks a gal.

BUT pcm says "off road", void warr ??

id need some hard proof b4 i pass the loot!!

i think hard tires and a soft foot are primary,, and i only go so long with the soft foot!!

so i readjust my priorities, like i quit pepsi, about 100 bucks a month so i can put that in the tank. also about $30 cheese snacks. pack my lunch, appx $7-10 any day,,,that alone buys my gas for that day.

i got a double cheese and fries, the burger was worth 1.39 but the fries are NOT worth $2+ so i cut the fries.

may sound dumb but i like feeding my h3,,gas AND good oil changes

tom

 

thanks for the input. Like I said, I know I bought a hummer and dont expect good mileage. But the cons of the beautiful vehicle more than make up for the bad mileage. I'm just hoping to squeeze out another 2-4mpg somewhere if possible and figured with the experience on here that about everything had been tried and tested.

 

Slumlord, I've read up on the PCM and it seems like a good idea. It also seems like some people go with the jet module. Any tried or true benefits over the other with those two products? With the PCM would i need to have all my mods done before I got the product so that it could be a true tune to my specified mods? I'm a newb and I have no experience or idea with what is best for these vehicles.

 

Remove the roof rack if you do a lot of highway driving.

 

Keep your foot out of it! No matter what mods, you wont get DRASTIC changes, maybe a mile or 2 better. I would start with a better air filter and the AIR-DOC. (my next purchase) i run the Jet Module and i am taking advantage of the better, smoother acceleration so i doubt i'm saving gas.

 

Yes, make all your upgrades before sending in your PCM, they will send you a OEM loaner to use for the week while they are reprogramming yours. They will also correct your odometer for the size tires you have.

 

pcm4less actually advertises 2-4mpg or so better?? I know the jet guys claim there is no difference but pcm4less will make an mpg difference??