2008/2009 owners..... Premium fuel question??

[splne1]

Yep I agree!! On my many trips back home to Texas I can definently tell the difference when premium is in the tank. I have towed some sand toys around back home and yes the difference is noticeable.

[pat123]

I have only had my H2 for about three months but I only use 93 octane fuel (I just got used to it with the 2007 Vette that I traded for the Hummer) so I do not know how well or poorly it runs on lower octane. I only drive mine on the weekends so paying for premium fuel is not that big a deal to me.

[MVR 155]

Splne 1..... with being on the road do you notice any improvement in gas mileage running the higher octane? Im sure any gain is offset by the higher price of the fuel but I was simply curious. Thanks

[dvl57]

I've filled my 08 w/regular 89 octane and had no issues.

I've tried using premium 93 octane...but I didn't notice any difference.

Then again, I never towed anything.


My Hummer dealer in Houston said it runs the same...w/regular as premium.

Who knows?! It could be preference or opinions...but I always tend to use regular.

[splne1]

Originally Posted by MVR 155

Splne 1..... with being on the road do you notice any improvement in gas mileage running the higher octane? Im sure any gain is offset by the higher price of the fuel but I was simply curious. Thanks

On cruise control it gains maybe 2 MPG's but nothing really to Jump about. But remember I am running it lifted on these big 37's. I also have a Hypertech programmer installed with the K&N intake. Im sure if it was stock height I could possibly get better MPG's.

[VegasGuy]

Don't underestimate the placebo effect.

[MVR 155]

Vegas....... Im well aware of the Placebo effect, have owned alot of modded cars/bikes and dont usually count horsepower till I see it on a dyno or get results at the track. I too laugh at posts on forums about the guy who installs a K/N filter and can feel a "HUGE" boost in horsepower....

Im not talking a night/day difference but there is a noticeably better response in the lower RPM along with the trans acting better.

I owned an 06 prior to this 08 and running premium did nothing in that truck so I can see how you may make the "placebo" statement based on the fact that you own a 2005..... there have been past threads here regarding the use of premium in the 2008/2009's due to knock issues, rough idle, low RPM gear hunting and clunking etc....

[seventwozero]

FWIW, When I bought my 04' the salesman told me because of the 6.0 a 'top tier fuel' should be used, nothing cheap! I've personally never tried it albeit I have a 800 mi road trip in a couple weeks, I'll give some premo fuel from Minneapolis a shot on my run home and see if it makes a difference. Top Tier stations are few and far between up here in the Dakotas, cheapo Tesoro and BP