Tahoe Hybrid By ALAN GELL (9/07) www.CarColumns.Net I recently had a short trip to see all the new General Motors products that will soon be coming on the market.  It was called the “Collection” event and included re-designed and updated vehicles as well as some brand-new ones.  The one that caught my attention the most was the all-new Chevy Tahoe Hybrid

The Chevy Tahoe is built in the DFW area at the Arlington assembly plant. That’s the plant located on Hwy 360 just south of Six Flags.  I’ve previously been on tours at this plant and the operation there is very impressive.  The plant recently celebrated their 50th Anniversary and the workers are very loyal and dedicated.
There have been a number of GM vehicles produced at this plant over the years, but the Chevy Tahoe is the current product.

The Tahoe is a full-size SUV that has earned an outstanding reputation from consumers. It provides terrific utility and versatility that today’s SUV owners need and want. Now, General Motors is taking the product one step more.  They are introducing a Hybrid model.

The Chevy Tahoe Hybrid is implementing a 2-mode Hybrid propulsion system that boosts fuel economy about 40 percent.  The functionality, comfort, design, towing – all that – isn’t sacrificed in this 2 mode Hybrid at all.  But, it is the 2-mode concept that got my attention most.

Mark Cieslak, the Tahoe Chief Engineer, was at the press event and I was able to spend a lot of one-on-one time with him.  A fascinating and dedicated engineer, Mark is passionate about this new Tahoe and the 2-mode system.  The oversimplified explanation is that it is like having a first gear and a second gear.  The first mode gives you a combination of either full-electric, full gasoline, or a combination of both.  This is the typical hybrid system, which saves a lot of gas at low speeds and in heavy stop-and-go traffic.  The second mode is the unique phase, where faster highway driving, heavy loads, or towing is necessary. 

The electrical system has motors that use 3 planetary gear systems.  Mark said this is one the key features.  General Motors is using mechanical links, which is obviously very efficient, while most other manufacturers are using electrically controlled links.  When more power is needed in a typical one mode, electrical link system, the gas motors run almost constantly, which is not as fuel efficient.  The GM motors using the mechanical links and the 3 planetary gear systems allow the vehicle to operate with only 4 cylinders for a long period of time, even at higher highway speeds and with heavier loads.  When the additional power is needed for passing or for heavier towing, then the other cylinders are activated.

I’m not quite sure I understood everything that Mark Cieslak was trying to explain to me, so I took the new Tahoe Hybrid out for a test drive.  I drove it along Interstate Highways as well as some really narrow and winding roads in the Nashville, Tennessee area.   Bottom line – you never know when the Hybrid is switching over from mode one to mode two or from four cylinders to the full V-8 mode.  It is a very seamless
and smooth transition.  There is a display on the instrument panel, if you want the information, which will show the Hybrid system’s functions.  I found it to be more distracting than anything. 

Mark told me that the hybrid batteries are designed to last the life of the car. The Tahoe comes with a five year, hundred thousand mile warranty that is transferable. The batteries are air cooled, which protects them and extends their life.  The design team implemented some significant aerodynamic changes to not only provide a sleek appearance to the Tahoe, but help fuel economy.  This included shaping the leading edges of the hood, flared running boards, and using aluminum for the hood and liftgate. Most of the changes made for the Hybrid were also implemented in the regular Tahoe. The Arlington assembly plant integrates the Hybrid into their regular Tahoe assembly line.

This new 2008 Tahoe Hybrid is certainly designed for fuel efficiency.  The two-mode system isn’t new.  It has been used for many years in some city bus fleets.  But this is the first introduction of the two-mode hybrid system into a consumer-based vehicle.  For those who want a full-sized SUV, no lack of power or capability, terrific fuel economy – all this – and benefit the environment, check out the new Tahoe Hybrid at your Chevrolet dealership.  I know I was impressed and know you will be also