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Chrysler Announces Hybrid Version of New Aspen Full-Size SUV

MY 2007 Aspen.

The new Aspen full-size SUV will join the Dodge Durango as Chrysler’s first volume production hybrids next year. Both vehicles will use a 5.7-liter HEMI engine coupled with the advanced two-mode hybrid technology being co-developed by GM, DaimlerChrysler and BMW (earlier post).

The HEMI engine will continue to feature Chrysler Group’s Multi-displacement System (MDS), which allows the engine to alternate between four-cylinder mode when less power is needed and V-8 mode when more power is in demand.

The new 5.7-liter HEMI Hybrid is expected to deliver an overall fuel economy improvement of more than 25%, including an improvement of nearly 40% in the city. The current 2007 Aspen (2WD) carries an EPA rating of 15 mpg city, 20 mpg highway, 17 mpg combined.

The advanced two-mode hybrid system is optimized for use in a large SUV or pickup, with a particular focus on being able to support towing applications.

The two-mode system is an electrically variable transmission which uses two electric motors to operate at any nearly any speed ratio through the transmission. The electric motors support hybrid functions: electric vehicle operation, electric boost and regenerative braking, as well as engine starting.

The two-mode system also is an automatic transmission, without the torque converter but with conventional hydraulically-applied wet plate clutches to allow automatic shifting among two continuously variable modes and four fixed gears for a total of six mechanical configurations.

Towing puts an especially heavy load in two main areas: increased steady state cruising and increased grade loads. The fixed gears in the two-mode increase the ability of the system to support towing without excessive electrical path losses or motor heating.

Typically, the increased road load would force a conventional transmission top operate near a 1:1 ratio condition for highway cruise...The fixed gear 3 [in the two-mode] with a ratio of 1.0 provides optimum fuel economy for trailer cruise by reducing the need to process power electrically. Fixed gear 2, with a ratio of 1.7, is useful for trailering on a grade at highway speeds, and fixed gear 1, with a ratio of 3.69, provide high torque to accelerate the vehicle at low speeds.

—“Defining the General Motors 2-Mode Hybrid Transmission”

With all the complexity and possible choices, the key to the success, including the driver experience, of the two-mode is the control system, according to Tim Grewe, GM’s chief engineer for the two-mode hybrid system. Full rule-based on-line optimizers are constantly (100 times per second) searching for the best efficiency.

GM is rolling out its own full-size SUV hybrids late this year.


  • Defining the General Motors 2-Mode Hybrid Transmission (SAE 2007-01-0273)



Glad to see the hybrid option.

Not too happy that it is yet another NEW behemoth on the roads.

It would be even better if ALL Aspen models were only available as a full hybrid...but that is unlikely anytime in the near term and they just want profits.

If luxury SUVs with crap gas mileage didn't sell so well, Chrysler would not even bother with this thing. I wonder what the 2008 mileage figures for the standard HEMI 5.7L 2WD Aspen is?


These huge SUVs still weight tons and have a large frontal wind resistance area; they are not going to sell to people who know about the penalties they pay for all that extra metal and the added wind resistance. Think how efficient this product would be if it were downsized to drop all that extra poundage. Perhaps the big three got caught with the wrong products in the production pipeline and they are scrambling to put out interim solutions.

As the price of fuel continues to increase

Mark A

I guess the "Hemi" makes it all right!!


Wow, a 15 mpg hybrid, this makes me want to cry. I don't even want to think about what it would normally get.


i´ll freak out if chrysler will be sold by Daimler in May...then will come up with all this good stuff making a "quantum leap" in engineering and making profits in 5 years and then being resold for 10times the price of today


I think Chrysler is barking up the right tree here with the idea of a 2-mode hybrid. I give them credit when they could have just tried to keep pushing these 2 models with incentives and their "business as usual" large gas engines. Instead they are making an effort towards efficiency, and in a class of vehicles where that is usually considered a dirty word. Many will say that it is too little, too late, and this will not amount to significant savings. I think it is better to offer people good choices such as this, rather than just write off all SUV's and Pick-ups as hopeless and evil.

Hopefully they did their homework with the Hybrid system--hope it works! If we could get this 2 mode hybrid system perhaps coupled with a diesel, and put it in the large SUV's and Pick-ups, they might really have something there.


Brad, the article says the current Aspen is rated at 15 mpg. If you get the upto 40% increase via the hybrid, that bumps it up to an amazing 21 mpg!


It also gets all these electrical components into the supply pipeline.These vehicles will begin to supply on the road data to hopefully prove the concepts.With success it will broaden to other platforms and push the others to be more bold with their offerings.
Toyota is advertising the heck out of the Tundra here so I dont think wishing away the larger vehicles is practical.Selling the hybrid extra costs may have to filter down from larger more expensive brands due to the lecacy costs.


There is still a large market for "luxury SUVs". Really, the large SUVs that were truck based and were not targeted at luxury buyers are the ones that are having sales problems.

People still love to buy their Escalades and Navigators so they can have all the "bling" and show the neighborhood that they can throw down money.


Few will be elated about the vehicle itself. It is still huge, heavy, and not especially desirable.

But it is better to launch what you can and then improve it than to await the fantasy of perfection.

I think their next move will replace that hemi with a turbo diesel for a 30%+ mileage increase. Diesels are one area where Chrysler is not behind.


heres another car thats going to help save the planet !

Harvey D.


Very funny!!!

Wonder if the flesh and blood dinosaurs fought as hard to survive?


Last month we all were rejoicing at the increased sales of the Prius and its other Hybrid brethren, but what we aren't acknowledging is that there is still a very, very large market for large SUV's and Pick-ups. This is going to sound like a concession, but here goes anyway: Since people WANT large pick-ups and SUV's, why not give them what they want, but try harder to make them more efficient? This goes along with the "Provide them with good choices" comment I posted above. I think there are still quite a few things to be implemented, (this 2-mode Hybrid for starters), that can get us to a better place in terms of efficiency. I have often wondered how difficult would it be to make an entire vehicle virtually of plastic? You would think you could do most of the hood, body panels, and chassis members out of plastic, and design "flex points" as sort of shock absorbers for crashes, (think crumple zones). Just an idea but maybe food for thought. I wonder if any automakers read our posts? Does anyone know? Is anyone out there reading this affiliated with an automaker? Come to think of it, if any Automakers do read these posts, they would probably never admit it due to all of the hate/bashing that goes on here on a daily basis.


PFD rules apply. The best life preserver is the one you are actually wearing when you go overboard. The best life preserver in the world is worthless if it’s so impractical that you can’t work in it; that life preserver will be resting on your bunk when you go overboard.

I can’t have a Prius. I can’t work in it. It’s not large enough. If you want me to get on the hybrid bandwagon, you need to get off your high horse and let them build a hybrid that I can actually use.


As I have said before, I have a 1989 Toyota land cruiser with
a 2500 cc5 cylinder diesel which still flys through the emission
tests and is able to return 30mpg, and if you need to pull a
tree stump out , snap it into low range and out it comes!
This car has no complicated engine management , in fact
it has no electronics at all !
Dont get me wrong I am not just bashing American products
although there does seem to be a level of unconsciousness within
the american industry that is particually worring , over here in
europe some of the products from Land Rover for example are
equally insensitive to the current predicament the planet finds
itself in . No amount of taxation will stop people wanting to own
monsters like this one , here in my small town in northern italy
we have two american SUVs, and strangely they are both driven
by guys whos vertical prowess does not exceed five feet !

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