gas mph 05 vs 08

[TGCOFTN]

I have a 2007 & 2008 H2.......and to be honest, I am not impressed with the 08's fuel economy at all. I could be wrong, but I dont think something is right on my engine on the 08, it seems so WEAK to have 393hp. I can take the 07 and go up hills without downshifting, and the 08 has to downshift on pretty much every hill when it has more horse and more torque. When I first got my 08, I did hit 19 mpg with it one time, but now, I cant seem to get it over 14mpg. I am gonna take it to the dealer and let them check it out. I really dont see any differences between the 6.0 and 6.2 in fuel economy cause with my 6.0 I have gotten as much as 18mpg with it.
Most will say its impossible, but as long as you keep it around 55---57mph on the interstate with the cruise on, it will do it.

[Stainless]

I am usually easy on the pedal and only getting about 12.2 avg!

[mikejr]

Originally Posted by TGCOFTN

I have a 2007 & 2008 H2.......and to be honest, I am not impressed with the 08's fuel economy at all. I could be wrong, but I dont think something is right on my engine on the 08, it seems so WEAK to have 393hp. I can take the 07 and go up hills without downshifting, and the 08 has to downshift on pretty much every hill when it has more horse and more torque. When I first got my 08, I did hit 19 mpg with it one time, but now, I cant seem to get it over 14mpg. I am gonna take it to the dealer and let them check it out. I really dont see any differences between the 6.0 and 6.2 in fuel economy cause with my 6.0 I have gotten as much as 18mpg with it.
Most will say its impossible, but as long as you keep it around 55---57mph on the interstate with the cruise on, it will do it.

Dont forget since the 08 has the 6 speed transmission it is going to shift more than the 07 that doesnt have the 6 speed tranny.

[HummerJim]

I've done my last three fillups(each 25 gallons or more) with 89 octane on my '08 and have found it to be better at idle and under WOT than the 87 octane and not much difference from using 91 octane. Mileage has been almost identical to the 91 octane, averaging around 12.0 with more than average highway driving.

[TGCOFTN]

Originally Posted by mikejr

Dont forget since the 08 has the 6 speed transmission it is going to shift more than the 07 that doesnt have the 6 speed tranny.

I remember it has the 6 speed tranny, but before I actually purchased it, I test drove a Cadillac Escalade ESV (for a whole week) with the same 6.2 and 6 speed tranny, and I remember bragging about how STRONG the engine felt and I dont remember it downshifting so much. I put close to 900 miles on the Escalade so I got a good felt of the engine) After comparing the Escalade to my 2007 Hummer, I decided I would go with another Hummer. The Escalade is a very nice vehicle, but its NOT a Hummer.
When my 2008 see's a hill, it gets scared before it gets a fourth of the way up it, and downshifts to like 2,400rpms like its starving for power and I am sitting there looking at the RPM gauge thinking to myself, how can this thing be more fuel efficent than a 2007 model. I am completely sold on a Hummer, and I would never want another vehicle besides a Hummer (which is why I have two H2's ) They are all around great vehicles and very comfortable on road trips. They are fun to drive, and to be honest, I cant say anything bad about them. I am not complaining at all about them, its just I dont really dont think my engine is right, I am going to go to my dealer this week, and borrow another H2 for a few hours, and put someone else in my 2008 and ride back behind it keeping the other person on a cell phone and checking to see how it performs, cause if its running right, they should both downshift about the same time on the same hill. I am going to get on the highway and put both of them on cruise control at 60mph and see if the Demo downshifts as much as mine. One day when I was pulling out of the gas station, the engine actually died on me, and I had to restart it, and it spit and sputter for about 30 seconds and cleared up. I run nothing but premium fuel in it, and pretty much use 95% Shell Gasoline. The other 5% being BP Gas.
Right now, it has 5,400 miles on it.......my 2007 is pushing 25,000 miles and has never had a problem out of it.

[HummerJim]

The biggest reason is WEIGHT, the curb weight on the 2008 AWD Escalade is 5565 lbs vs 6400 lbs. for the Hummer H2. The axle ratios are different too with the Escalade's 3.42 vs. the Hummer's 3.73. There is a previous thread about the Escalade and Hummer having different shift chips for the Hydra-matic 6L80, also the Escalade is more aerodynamic without the trademark Hummer, almost vertical windshield. I've notice a slight improvement in highway mpgs for the H2 by removing the roof racks, which I never use and making it easier to fit in some parking garages.
This weekend gasoline @ $2.19 a gallon at Walmart in Washington, MO and $2.42 for premium. They had cars lined up for 200 ft., even though it was $2.29 at the BP across the street.