ZX1100F1

The GMT900 Tahoe has a coefficient of drag of just .36
The Hybrid's Cd is .34
the Ford Focus is .32 and a Corvette .29 for comparison sake.

in2pro

What makes up the .02 difference of the Tahoe's?Same body style right, Iguess if you took of the roof rack you could reduce drag some and streamlining any protrusions underneath the body. The real question is does waxing your vehicle make any difference...

ZX1100F1

The Hybrid also has slipperier front and rear clips and a drag redcuing rear hatch halo and side skirts.

Waxing your Tahoe does make a difference..............just not in fuel economy.

gdf7279

Here's my two cents... I purchased the Tahoe over the Saquoa and Armada because of the advertised MPG. I also have friends with both Saquoas and Armadas and all in all, I think I get the better MPG, which is great. My only gripe about the AFM is that I think it could go into V4 mode more than it does. I understand that when I start moving I want to be in V8 mode, but I also notice that as soon as I hit the gas the truck always jumps right into V8 mode. So why couldn't they make it Idle in V4 mode and jump into V8 mode when you start moving? Also, I've noticed often on down hills the truck will stay in V8 mode when it is just coasting down.

Don't get me wrong, I think the AFM is great considering what it does, but I think they could have done a few things to squeeze out a little better MPG with the AFM.

in2pro

I understand GM not wanting to compromise any performace for the AFM by not going into V4 or staying in V4 any longer then needed but sometimes I just need to adjust my foot or just barely nuge the throttle and it would be nice to keep that V4 for just a half second more.

gdf7279

Cruise control will help with that... don't have to worry about your little foot ticks or adjustments you need to make... I'm in V4 mode far more when in cruise control then when controlling speed myself...

in2pro

Yup that would be a true statement, here is a quote from an artical I was reading about cruise control and MPGyesterday...

"5. Use Cruise Control
Letting your car's computer control the speed is a win-win for laziness and the environment. Most tips for improving gas mileage require some work on your part, like keeping your tires inflated properly (which can improve mileage by 3 percent and save about 250 pounds of CO2 annually for the average driver).[/align]But you might double that improvement just by relaxing with cruise control. Tests by edmunds.com found that using cruise control improved mileage by 7 percent. (One exception: Cruise control can use more gas if you're driving in very hilly terrain.)[/align]Even more savings are possible if you've got a car with the new "adaptive cruise control" that uses radar or lasers to keep you at a safe distance from other cars. The more drivers who use these systems, the more smoothly traffic flows, resulting in less congestion and therefore less fuel wasted."[/align]


Okay ZX when is the General coming out with the "adaptive cruise control"

73shark

You can answer this question by going out and pulling four plug wires off and let 'er idle.

On a more serious note, I've found that using tow mode in town will keep it in V4 mode more and yields better mpg even tho the rpm will be higher (unlocks torque convertor). I've tried this both ways on the same stretch of road and found it to be true. A tail wind helps big time.

2007TahoeLTZ4x4

when your under 40mph the biggest hurdle that your car has is to get the wheels rolling (think about how heavy your car is and trying to push it yourself vs when your on the hwy the momentum reduces that effect) this is why keeping your tires properly inflated can help so much...after that the wind resistance over takes the rolling resistance of your tires...why do you think they say that its more fuel efficient to use your a/c on the hwy rather than rolling your windows down

2007TahoeLTZ4x4

also...what do you mean by saying that the Tow/Hual Mode unlocks your torque converter? ive noticed that shifts are much more firm and that it does stay in v4 mode longer but i dot know if it could cause problems in the long run...course i guess we dont know about switching between 8 and 4 cylinders either