http://www.freep.com/apps/pbcs.dll/a...802210312/1081

A nice review and what I've been looking for.

Bob Wilson

Operation Iraqi Oil Freedom:

Automatic, stock, project car.

My other 1500 cc car:

Automatic, stock, backup car.
Free speech, dialog and knowledge thrives without the poison of SPAM.

I appreciate the mention of the idea that it could save more fuel gallons (compared to the non-hybrid version), than a Prius (compared to...um I don't know, but tha's not the point).

It's completely correct though mathematically subtle that adding 5 mpg at 20 mpg matters more than adding 5 mpg at 50.

Our departed hero Dave Hermance made the same point in many public presentations.

We need to save fuel in all vehicle classes. Build the best ones you can! Buyers, choose the most economical vehicle that does what you need done.

Everything else is "styling".

DAS

"GM calls the system a two-mode hybrid because it improves fuel economy both in city and highway driving. Other hybrid systems reduce fuel consumption in city driving, but have no effect at highway speeds.
The rear-drive hybrid Tahoe rated 21 m.p.g. in the city and 22 m.p.g. on the highway in EPA fuel economy tests. That compares with 14 m.p.g. city and 20 m.p.g. highway for a similar gasoline-only Tahoe."

Wrong. The Prius is fully ulitizing electricity all the time to further efficiency, even on highways. Duh.

And 22 MPG is certanly better than 20 MPG (highway), but at the expense of higher overall emissions? See the attched .pdf.

THAT is simply stupid.

And 50 grand for a marginally more efficient vehicle that is dirtier? who are these suckers who will buy this? How does this get into the hands of many, to really make a difference? A limited market with limited availability? Wow, and I thought it couldn't get any worse.

I'm sorry, but GM is laying yet another crap-brick. I'm just not a big fan and need to rant. YMMV.

Attached Images

TahoeHybridEmissions.pdf (92.4 KB, 3 views)

'04 Seaside Pearl #7. Fumoto oil drain, mudflaps, rear bumper scuff protector & rear warn system, compass mirror, EV mode button, 8" subwoofer in right rear cubby & 6" subs under seats, power lumbar in the front seats, Coastaletech hitch w/ Aspen bike/snowboard rack. iPod2car, 2 amps, Alpine component speakers, and DVD video, solid 47 MPG @ 70000 miles.

Tangential comment, and only to completely agree with Finman. The Prius electic CVT (which has many other names) allows the gasoline engine to be operated in (or darn near) its highest efficiency over a huge range of load and vehicle speed conditions. This is a major contribution to its overall efficiency.

Other hybrid (and 'hybrid') systems may do much less towards the goal. Or should I say The Goal.

DAS

With the exception of GM's hybrids I thought both Honda/Toyota systems currently feature highway savings features.

Just looking at my car:
1) Smaller engine that gas only version means more savings over the same distance travelled.
2) Fuel cutoff when gliding/coasting, works on the highway as well. The only gas only cars with fuel cutoff just reduce the # of cylinders active to 2 or 3.

Indeed, the reduced displacement, Atkinson cycle, CVT ratios, LRR tires, and improved aerodynamics of some hybrids improve highway fuel economy. GM's dual-mode system adds to that a planetary set of four fixed gears that provides a direct mechanical path for the electricity.

The Tahoe's additional 2 MPG on the highway is rare among heavier hybrids. With HSD on the LS and GS, highway fuel economy drops by 2 MPG.

Yes.
Somehow this slips everyone's mind, but the numbers don't lie. You can look at driver results (like MINE, for example ), or just get EPA test results direct from the government.
http://www.fueleconomy.gov

Checking some out:
2008 Civic 4dr sedan:
Regular - 25 city/36 hwy
Hybrid - 40 city/45 hwy (no comparison!)

2008 Altima
Regular - 23 city/31 hwy
Hybrid - 35 city/33 hwy (close, but still better)

2008 Camry
Regular - 21 city/31 hwy
Hybrid - 33 city/34 hwy

2008 Highlander 4WD
Regular - 17 city/23 hwy
Hybrid - 27 city/25 hwy (quite close, but still better)

2008 Ford Escape FWD
Regular - 20 city/26 hwy
Hybrid - 34 city/30 hwy

2008 Ford Escape 4WD
Regular - 19 city/24 hwy
Hybrid - 29 city/27 hwy

HOW IS THAT NOT BETTER ON THE HIGHWAY?
Now it's certainly not AS MUCH % BETTER as is the CITY MPG. But to say there is no improvement is a LIE (except for maybe some of GM's offerings). I can only presume that nailing the gist of the (usually) limited improvement on the highway was the intent.

Steve

STOP terrorism - Drive a HYBRID

Vehicles:
350 miles a week ------------ 2006 HCH II, Magnetic Pearl, w/NAVI (born on May 25, 2006)
350 miles a month ---------- 2003 Mazda Tribute ES-V6
350 miles a year (for now) - 1986 Mercedes 560SL

I know everyone keeps looking at the highway numbers, but some of us urbanites do mostly city driving. I know there are a lot of SUV drivers out there who are driving them because of the 'cool' factor, but there are also individuals who have legitimate needs for such a vehicle.

At this point, the fact that an opportunity for improvement exists is a good thing. I'm not joining in the GM bashing.

To me, the ultimate hybrid would be a 15-passenger van, a minivan or a Suburban (filled with stuff of course). That truly maximizes the people/cargo per vehicle per mpg.

IMO there should be no mud slung at GM on its first real entry into the Hybrid Derby. This technology is every bit as effective as Toyota's or Ford's or Honda's.

I've noted it here several times ( parrotted by the author as well ) that for an SUV driver this vehicle does save more fuel than moving from a Civic to an HCH or a Camry to a TCH. Remember no other vehicle makers has been able to make a 6000# hybrid yet. As noted previously it is far far more important to solve our biggest problem first; i.e. improving the least efficient vehicles. Much more fuel will be saved, less money will be spent and less emissions will be generated if we address SUVs and trucks as the primary problems today.

The two really important issues facing us as a driving population are improving the City driving mode of all vehicles ( the least efficient mode ) and improving the least efficient vehicles as a group. These first 2-Modes do both admirably. Both of these are far more important than increasing the Prius from 48 mpg to 60 mpg.

BTW the market for fuel prices will take care of the problem of too many 'image' owners of trucks and SUVs. Since the end of 2003 more than 1 million buyers annually have already 'parked' their gas guzzlers in favor of buying something more efficient. As fuel goes to $4 or $6 or $10 a gallon in the next 5-15 yrs these big rigs will naturally die out like dinosaurs. What will be left are those few big rigs that are needed imperatively. Those vehiclles will be very very efficient by today's standards ( 26-30 mpg? ).

Lifetime fuel usage: 2.1 GPC ( 1.99 recent )