A Gear Box On Wheels

A Gear Box On Wheels

Phil Berg

You can’t drive your house, but you can live in your car — if it’s Pontiac’s 2001 Aztek. With this vehicle, GM moves into the gear-and-accessories business.

“It looks like what people who drive an Explorer in the city should drive,” says Jeanie, a young, cheery resident of outdoorsy Truckee, Calif., when she first spots the Pontiac Aztek.

“This is versatility wrapped in a bold package,” offers Pontiac Brand Manager Don Butler.

“It’s butt-ugly,” say many who have seen Aztek on this year’s auto show circuit.

Like it or hate it, General Motors’ first “crossover” vehicle in North America breaks plenty of new ground. The Pontiac Aztek (GMT250) is based on GM’s U-van Montana/Venture/Silhouette platform, with a one-inch-wider track and four-inches-shorter wheelbase. It’s aimed at early 30’s couples who actually do lots of recreational activities, rather than just buy the equipment. These people don’t like the “mom’s van” styling and image of a minivan, but want more interior space and better ride quality than a sport-utility.

Perhaps Aztek is best described as a tall wagon, incorporating design traits of both minivans (front-wheel drive and hatchback) and SUVs (four conventional side doors, a small tailgate and a center console that’s too bulky for a front passenger to walk through to the rear seats). Competitors developing their own crossover vehicles will find it worth scrutinizing in two key areas: interior flexibility and the mind-boggling array of optional “stuff” — lifestyle-oriented gear developed through GM Service Parts Operations (see box, p. 68)

Pontiac claims 94 cubic feet of cargo area with the rear seats removed, which is significantly larger maximum cargo capacity than the nine-inch longer Dodge Durango, which holds 88 cubic feet with its non-removable seats folded flat. The short wheelbase Montana minivan, which is almost five inches longer than the Aztek, however, will hold 133 cubic feet. The Aztek is two inches wider than a Durango, and will fit a four-by-eight sheet with its tailgate down. To give the vehicle a trimmer and more agile appearance, the rear overhang was reduced almost five inches from that of the short Montana’s. Still, this is no compact — Aztek makes a shadow on the ground five inches wider and longer than a Honda CR-V.

(For more information on the GMT250 program and its U-van cousins, read our March feature on AI’s website at (www.ai-online.com/articles/march00/0300f9.htm)

While many consider Aztek’s styling to be polarizing at best, a surprising number of consumers we polled on the street called it “cute,” during the vehicle’s official media debut in California. Some of that reaction may come from what Chief Engineer Charles Kingsley says was the most critical styling decision: to slope the rear hatch so it wouldn’t look like a minivan. The fast C- and D-pillars were designed to allow two mountain bikes to stand up inside. Once the angle of the rear roof and hatch was established, a tailgate was the only solution to keep the hatch from growing too large and heavy.

Kingsley notes that some customers like to use tailgates as seats and support for extra-sized objects, but others complain that they don’t want to lift cargo over a tailgate to get it inside the wagon. To answer the latter group’s grumbles, a rolling loading tray is offered (see “Gear On Board,” below).

The angular look also comes from the body’s minimal tumblehome, which addresses customer desires for more shoulder room than is offered in smaller crossover vehicles, particularly the CR-V and Lexus RX300. Another styling concession was raising the floor and suspension (most of which comes from the Grand Prix sedan) 0.5-inch, for greater ground clearance. The downside of this change is that Aztek’s 15-inch Grand Prix-sized wheels (16-inch on GT and awd models) look too small under the body.

Gear On Board!

Two Aztek models are offered — plain ($21,995 base) and GT. The $24,995 GT is distinguished mostly by the larger wheels and tires, and adds rear climate vents, radio controls on the steering wheel, more driver and passenger front seat adjustments, some interior lamps, a trip computer and information display, and an assortment of amenities optional on the base Aztek. Unique to the GT is a clever console-mounted ice cooler. Later in the production cycle, a head-up display that includes stereo settings will be available. GM’s OnStar telematics system is available on the GT, but the optional sunroof must be deleted.

To save trips to aftermarket accessories stores, there are four packages that can be added to either model. The Towing, Camping, Biking, and Backpacking packages each come with unique equipment.

“We just turned everyone loose on brainstorming ideas for the equipment,” recalls Kingsley. Surveying the Aztek’s interior options is like paging through the REI outfitters catalog. The materials and hardware have been selected to appeal to gear junkies. Even the dash material is textured like the handle on a scuba-diving knife.

GM may interest Winnebago in the Aztek as a camping machine. You can actually live in this wagon, if you select the “Camping” package. It includes a tent, and fits over the Aztek’s open rear hatch. It takes only five minutes or so to attach to the wheelwells by bungee cords, and fits tight to keep out rain and bugs. The door under the raised hatchback has zippered screens for ventilation.

The camping package also includes a rectangular air mattress that covers the floor, and it’s thicker than necessary for backpackers — meaning it’s comfortable for those older than the Aztek’s target buyer. The two rear seats fold forward, leaving a flat load floor that can be extended by lowering the tailgate. With the tailgate down, the floor will double as a bed for two six-foot adults. The rear seats themselves recline, too, for catnaps.

There are bins and cubbies in the rear walls of the Aztek for a travel alarm clock, pocket knife and water bottle when you’re camping, and you can control the stereo from the rear, too. The back side of the console between the front seats has two 12-volt outlets, one for your phone and another for, perhaps, a Whistler 12-volt blender. There’s also another 12-volt outlet near the rear hatch. With one on the dash, the outlet total is four.

Aztek’s JCI-supplied rear seats weigh 45 pounds each. That’s about double the mass of a single rear seat in a Montana minivan, but maybe the more active-lifestyle Aztek customer will welcome the extra workout required to remove them.

Between the front seats is an integral, removable cooler. It is sized to contain a 12-pack of 12-ounce drink cans, and has a small tray for more snacks. The front of the cooler has a three-inch Pontiac “V” logo molded in, and the embossed logo fits into a corresponding “V” depression in the console. The handle of the cooler locks it into place in the console, and also locks the lid of the cooler.

“We went to Rubbermaid and Coleman, to see if they’d make us a cooler. But they don’t even consider production runs less than a million,” explains Kingsley. So GM had to find another less-known source.

An optional plastic tray will cover the rear cargo floor, and it can be unlatched and wheeled out onto the dropped tailgate. Pull the tray all the way out of the vehicle and there are wheels on the edge, so it can be rolled vertically into a garage. While in position as a tray, there are configurable dividers on the passenger-side half of the tray. On the driver-side half, a shallow covered box opens and can store jumper cables inside. A second option is a cargo net system that’s so extensive and configurable, it looks like a livestock pen for guinea pigs. We don’t doubt a resourceful customer will use it for that, either. Even without these options, the cargo area has 12 anchor hooks for tie-down straps.

The shape of the body owes itself to mountain bikes standing up in the back, and an optional inside fork mount attaches in place of the rear seats. Even so, the GT model gets a roof rack system from Thule, one of the two leading aftermarket roof system makers. The mounts were GM designed, and are specific to the Aztek.

“The same rack that’s quiet on one car isn’t on another,” notes Kingsley. This is due to windshield angle, he says. That means if you graft the rack onto a Montana, for example, it’ll be louder. The biking package adds the necessary hardware to carry bikes on the rack, or customers can choose the interior fork mount. With either system, deep rubber floormats and coated vinyl seat covers are included to protect the interior from muddy riders. The hiking package includes the covers and mats, and adds two daypacks that clip onto the backs of the front seats.

Optional on both models is a Pioneer-designed 190-watt, 10-speaker stereo designed to project sound to a 25-foot focal point behind the Aztek when the hatchback is open. It works, making it sound like you actually moved the speakers outside of the vehicle. When the hatch is closed, the sound quality is on par with premium GM systems. It’s the fast OEM system for Pioneer.

Aztek’s clever interior features and the intense focus on supporting a wide range of recreational activities are almost enough to make you ignore the weird-looking body. The attention to ride and handling (see www.ai-online for a drive review), as well as the no-compromise Versatrak four-wheel-drive option (priced as a package at an extra $3,000 over the GT), give Aztek a competitive performance advantage over current minivans, crossover wagons, and car-based sport-utilities.

In the early 1990s, Subaru wagons offered the same combination of innovative engineering and superior passenger comfort, but they didn’t start to sell well until plastic surgery made them handsome and rugged. The 2001 Aztek may face the same challenge.


With Aztek, GM aims to cash in on Americans’ love of outdoor and active-lifestyle “stuff.” The equipment for Aztek’s Backpacking, Biking, Camping and Towing packages will carry the “GM Accessories” brand, rather than separate name brands. It’s all being sourced through the automaker’s Service Parts Operation (SPO), based in Grand Blanc, Mich.

“This is a first for us, and we’ll continue it on other vehicles in the future,” says Susan Reyes-Nothoff of SPO. “With GM Accessories, we’re trying to create an `umbrella’ brand that, over time, customers will get to know and, we hope, prefer.”

For that reason, she won’t break out supplier names for Aztek’s gear. “They’re not well-known companies,” she says. “But you will see us offer popular name-brand gear in other vehicles. The 2001 Chevrolet Avalanche pickup will offer a North Face tent package, for example.” Look for new GM Accessory packages on the Chew Impala and Monte Carlo coming soon — we’ll bet with a NASCAR theme.

–Lindsay Brooke


A whole ‘lotta traction in a small package.

“There’s a certain image that goes with four-wheel-drive,” says Sharyn Yamblick-Cousins, Pontiac brand manager, enough that the option is expected to eventually be included on more than half of Aztek sales. To preserve the minivan-like efficiency and driveability of the Aztek, a four-wheel-drive system that is lightweight and could be packaged without sacrificing interior space was needed. Rather than use a viscous-coupled system like that of Chrysler’s minivan, GM opted for a new torque-sensing system with more traction, and that could be tuned for smoother response.

GM went to Steyr-Daimler-Puch of Graz, Austria, the builder and supplier of the Chrysler system. Steyr licenses the technology from ASHA Technologies, the Santa Barbara, CA-based technical design firm that owns McLaren Engines. ASHA pioneered a gerotor concept that was essentially a limited-slip coupling, with a rotary oil pump pressurizing a clutch pack attached to the pump.

First used in the 1999 Jeep Grand Cherokee, the gerotor system joined the mechanical torque-sensing market alongside the aftermarket Quaife (well known among racers) and the more popular Torsen differentials, which Audi made famous in its Quattro system.

Torque-sensing couplings or differentials are based on the theory that you never really need a fully locked differential, and that the difference in speeds between wheels on a vehicle can be harnessed to power the actions of a limited-slip unit.

The Jeep comes with three ASHA-type single gerotor couplings, one in each axle and one between both axles. This setup has the ability to move the vehicle if any of the four wheels has traction.

But two of these gerotor units side-by-side — a so-called “twin gerotor”– can replace a conventional axle differential altogether. Not only does this setup function as a limited-slip rear differential, but it can do extra duty as the center differential in a four-wheel-drive system, eliminating the need for a transfer case or decoupler between front and rear axles.

GM chose Steyr to package and help develop this “Twin Geromatic” system and calls it Versatrak. It will appear on the Aztek this fall, and on the Rendezvous in early 2001. The minivans will get it later in 2001 on 2002 models.

The Versatrak system engages without driver input, and shifts torque more gradually than a viscous coupling can when a front wheel spins. Two pressure-relief valves in each gerotor case control the actuation of the limited-slip function, and allow it to work as consistently in cold conditions, when the vehicle is first started, as it does when all fluids are warm. A fifth valve closes fluid intake to the gerotor pumps as a default, and can disengage the system when the ABS sensors detect the compact spare tire in use, for example.

With the Versatrak system, GM has a four-wheel-drivetrain that offers torque-sensing in the center and rear differentials, a capability only available on luxury cars — and greater than any other minivan or crossover vehicle on the market. –PB

COPYRIGHT 2000 Cahners Publishing Company

COPYRIGHT 2000 Gale Group