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Saturn Aura Green Line Hybrid to Offer 25% Fuel Economy Improvement Over Non-Hybrid

Aura Green Line Hybrid sedan. Click to enlarge.

GM formally introduced the Saturn Aura Green Line hybrid at the Los Angeles International Auto Show (earlier post). Based on the same GM Hybrid system as the VUE Green Line Hybrid (earlier post), the Aura Green Line sedan will deliver at least a 25% fuel economy improvement over the non-hybrid Aura XE for a premium of less than $2,500, according to GM.

The non-hybrid 2007 Aura XE, fitted with a 3.5-liter V-6 engine, carries a fuel economy rating of 20 mpg city, 30 mpg highway.

The Aura Green Line’s base price is expected to start below $23,000, and will be available at Saturn retailers in spring 2007.

The GM Hybrid Belt Alternator Starter (BAS) system in the Aura Green Line combines an electric motor/generator with a 2.4L Ecotec VVT four-cylinder engine, Hydra-Matic 4T45 four-speed transmission and Cobasys 36V NiMH battery pack.

The Saturn Aura Green Line is the first of four hybrids GM will introduce in the 2007 calendar year, more than any other manufacturer. Equipped with GM’s 2.4L, four-cylinder Ecotec engine and the GM Hybrid system, the Aura Green Line will deliver spirited performance, as well as a significant improvement in overall fuel economy compared to the current Aura.

—Tom Stephens, group vice president, GM Powertrain

Aura Green Line’s hybrid powertrain is rated at 164 hp (122 kW) at 6,400 rpm and 159 lb-ft (215 Nm) of peak torque at 5,000 rpm. The GM Hybrid system provides start-stop functionality, early fuel shut-off during deceleration, regenerative braking and intelligent battery charging.

The new GM Hybrid system also provides additional power when required during launch from the electric motor/generator. At wide-open throttle, such as during a passing maneuver, the system enhances acceleration by using the motor/generator to bolster the gasoline engine and achieve maximum power.

The GM Hybrid system also is designed to automatically maintain full accessory functionality when the vehicle is stopped, including climate control, so that hybrid operation is transparent to the driver and passengers. The Aura Green Line delivers an appropriate balance between fuel economy and cabin comfort with an air conditioning system with two selectable modes. The Hybrid A/C mode favors more fuel efficient performance by limiting the draw on the hybrid powertrain, while the normal mode provides maximum passenger comfort in hot climates and enhances defogging performance.

The Aura Green Line hybrid sedan is based on the all-new Aura midsize sedan. The Aura Green Line is one of 12 hybrid models GM has announced, providing customers with several levels of fuel economy savings across different brands at different price points on vehicles ranging from cars to full-size SUVs.



The Hollow Hybrid. It's a start/stop feature, not a full Hybrid.


I don't follow. I says it has a pack, regen braking, and an electric motor. What's hollow about it?


It is as much a hybrid as Honda's are. as it provides partial assist and regen, not just stop/start.

However the title is a little disenginous, as the 25% compares a v6 to a hybrid 4cyl... perhaps it should be changed to "4cyl hybrid to get 25% better than v6..." or simular?

Anyway, it is exciting to see GM bringing these technologies to market, the more companies offer hybrids the more mainstream they will become.


The mild hybrid features are ones that can benefit from mass production and be applied to a wider number of models. This would in turn raise overall cafe.
More sophisticated{expensive}systems are being employed in suv's.This exploits early adopter tactics that have worked in electronics and computer world.I am encouraged that this is beginning to resemble a bottom up ,top down plan.Any plan is better than the aimless meanderings of late.


This is the best GM can do when the management ignores the realities of the market. They wait until it is too late, then rush the engineers to get something..anything out.


As an investor in the battery manufacturer I'll take all the sales GM can generate and Royalties Toyota will pay on the Camry.


Yesplease, it is an improvement over not having any assist. My point was that an oversized alternater/motor and battery are not a full hybrid. I remember this technology being talked about 5-10 years ago. It's really a stop/start mechanism. The assist they speak of is small. Not running the engine in NYC traffic jams is good. But the Prius/Escape is a much better system. The advantade here is the lower cost and scalability to other platforms. This is a MILD hybrid, more of a stop/start idle reduction.

Lee Dekker

Better to spend some cash developing a halfhearted hybrid than spend it paying lawyers to fight clean air mandates. Unlike Toyota 's hybrids, this unit can't even creep along in electric only mode. That quiet electric running offered by Toyota hybrids gets people's attention and probably adds a great deal to their mystique. It's not clear to me if adding battery capacity and external charging to this vehicle would be feasible or improve mileage numbers. But the View is no different from any of the current hybrids, in that it derives 100% of its power from gasoline and makes no accommodations for any other energy input.
Only GM could come up with something like "green line". It makes one wonder what their other lines are called, Gray line ? Brown line?. It also sounds temporary. It's just damned hard to pat GM on the back for this vehicle. But it is better than a poke in the eye.

Ron Fischer

Dilutes 'The hybrid advantage' in the public eye. Combined with the new CAFE measurement regime the public will see vehicles for sale with the label 'hybrid' and a much smaller MPG advantage on the window sticker.


Andy, it's much more than stop/start.
Just because if falls short of the Prius doesn't make it garbage as a hybrid. Every hybrid now sold falls short of the prius.
It does have asstist in propulsion and does have regen on braking the tow major components of hybridizing.

Peter B

Any hybrid is better than none. And, 25% improvement is not all that bad - about what the Toyota SUV hybrids get and they are true hybrids. What is even more encouraging is GM's newly announced commitment to electic drives in cars - probably an all-electric in the future - as indicated by the recent speech of their CEO at the Auto Show. Fuel cell, hybrid and all-electric cars would be a big step forward.


Redline is their other "line". It is more performance oriented.

I hope it sells well and GM slowly puts idle-stop with mild assist on their entire lineup of vehicles.


Calculating price premiums and fuel economy boosts by comparing a 4 cylinder mild hybrid to a 6 cylinder non-hybrid?

Typical GM -- doing the accounting magic dance to hide how expensive and crappy their technology is.

I wonder sometimes if they don't make these things just to say, "See? It doesn't work."

Harvey D.


You called it correctly. GM is trying to fool buyers with this reduced hybrid technology and misleading fuel economy.

Wonder how many customers will fall for it. Remember what Winston Churchill said...

Toyota's hybrids are years ahead and getting better. The Prius III technology is what most people, who want better mpg, will want.


I think you guys are being overly harsh (and I'm a Toyota fan). Isn't the non-hybrid Aura available only in V-6??? If there isn't a regular 4 cyl. version, why get all bent out of shape over this hybrid?? A theorerical regular 4 cyl non-hybrid version would get maybe 10% better MPG than the 6 cyl version, so a 25% improvement is not bad.

And I'm assuming that the performance of the hybrid vs. non-hybrid will be comparable. So the end result is a car that has as good performance as the 6 cyl version, but get's 25% better MPG. And a good price point, so alot of people are likely to go hybrid. Not perfect, but it's a start. Plus it's better than not having any hybrid version available at all.


What does "early fuel shut-off during deceleration" mean? Don't all modern FI systems shut off fuel on coasting and deceleration?

Also, why the hate? This is an acknowledgment that maybe, just maybe, GM will have to get off its SUV habit. It's not state of the art, they need to bring in the Astra, it should be a 2.5 turbo instead of a 3.5 NA, etc etc, but it's better than same-old, same-old. It's good news. I hope it succeeds.


And I'm assuming that the performance of the hybrid vs. non-hybrid will be comparable.

They're not.

per the post:
"Aura Green Line’s hybrid powertrain is rated at 164 hp (122 kW) at 6,400 rpm and 159 lb-ft (215 Nm) of peak torque at 5,000 rpm."

The non-hybrid base Aura has 224 hp and 220 ft-lbs of torque.

Mike Z

I can really see the anti-GM Bias here:

Remember a Prius is basically a Corolla and the MPG improvement is around 25% in real world drive.


Also, why the hate?

Why is any legitimate criticism of a General Motors product, based on hard numbers, labeled as "hate"? You have it backwards. People get disappointed with General Motors because of what the hard numbers tell them.


I can really see the anti-GM Bias here

Heh - right on cue.

Remember a Prius is basically a Corolla and the MPG improvement is around 25% in real world drive.

A Prius isn't a hybrid Corolla. That's such a red herring.

mike z

Really: "With the Prius, says electrical engineer Michael Cutajar, "Toyota took a Corolla and added huge amounts of cost and complexity. They don't make any money on it.""


But while we're at it, Mike Z - let's run the numbers.

Corolla - 33 mpg (EPA), 27.2 mpg (user reported)

Prius - 55 mpg (EPA), 46.9 (user reported)

So, the Prius gets 67% mileage per EPA numbers and 72% better mileage per user-reported numbers.

By comparison, the 2.4L Ecotec in a comparable vehicle to the Aura gets 27 mpg.

The non-hybrid Aura is rated at 24 mpg. A 25% improvement over that is 30 mpg. So, this new Aura will improve fuel economy by 11%.

Thanks for your help.


Really: "With the Prius, says electrical engineer Michael Cutajar, "Toyota took a Corolla and added huge amounts of cost and complexity. They don't make any money on it.""

And the following sentence says "Toyota scoffs at the idea. "We're making money on the Prius."

Thanks again.


The "Green Line" Lineup of vehicles are basically high end micro-hybrids. If you consider them mild-hybrids, they would be marginal at best. Honda's IMA is a better mild-hybrid system. The start-stop capability would help in city driving (esp gridlock), and the systems/accessories running off of electric motors also helps overall fuel economy.
_The full shift from mechanical to electric drive, of accessories and pumps(AC to coolant to superchargers), would provide another 2-5% bump up to fuel economy.


2007-2011 is the timeframe for the rollout of many Green Line, 2-mode HEV, 2-mode PHEV, and Tier2Bin5 diesel vehicles from GM and DiamlerChrysler.

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