1998 Sierra Ace
GMC Sierra ACE Show Truck Represents New Standard for Full-Size Pickups
DETROIT - In most card games, the ace is the primary and highest card in the deck. In the full-size pickup truck gram, GMC's new extended cab Sierra show truck is the ACE.
ACE is for Advanced Concept Execution, and it gives a peek at the hand GMC will be playing in the full-size pickup segment for 1999. It's the new translation of Sierra's promise to deliver strength and power with style.
"The Sierra ACE demonstrates a strong product expression and provides a glimpse of GMC's next generation full-size pickup," said Sierra Brand Manager Jim Kornas. "With its aggressive appearance and surprising capabilities, this show truck reveals how Sierra will set a new standard for full-size pickups as we enter the twenty-first century."
A Unique Show Truck
Resplendent in its unique Platinum exterior color, the Sierra ACE has the flare of a show truck, but offers a customer-pleasing functionality including some innovative uses of cargo box space.
More Light, Less Glare
Much of the front-end design character of the Sierra ACE is portrayed in the forward illumination systems, just as a person's eyes often reflect their inner self.
The ACE"s forward lamp configuration is deeper, wider and taller than those on previous Sierra pickups. Additionally, lighting engineers created a new lens "prescription" for accurate low beam focusing, but went to reflector optics for superior high-beam illumination. Both modes produce a highway-friendly light pattern with smooth, even pattern parameters to enhance the driver's feeling of comfort and safety.
Accurate Low Beam Focusing
In addition to providing a 30-percent increase in forward light range, the low beams of the new headlamps yield 120 percent more left-hand driving light for better visibility of obstacles near or to the left of the roadway centerline. These enhancements were accomplished without increasing the level of glare, much to the delight of drivers in oncoming traffic.
This exceptional combination of more light without increasing glare is the result of extensive use of computer program that simulates night road conditions. Engineers were able to perfectly tune the headlamp optics before a single lens was made.
Thanks to the new design and work with simulated enviroments, the headlamps of the Sierra Ace deliver 25 percent more high-beam illumination than previous Sierra headlamps but use the same amount of energy.
Circular Fog and Road Lamps
To further enhance the personality and forward illumination excellence of the Sierra ACE, designers appropriated and enlarged a feature from GMC's passenger car siblings at Pontiac-lower body circular fog and road lamps. Positioned in the lower valence area of the front fascia, the fog and road lamps enhance the aggressive styling of the GMC show truck while providing an unparalleled element of forward illumination and safety.
Chrome Accents
A Wide, expressive grille not only accentuates the powerful on-road stance, but also increases underhood airflow. The chrome bumper and unique ACE-specific chrome-plated tow hooks denote a strength and stylishness aimed at GMC full-size pickup buyers.
Side Cladding/Rear Fascia
Body-colored side cladding compliments the chrome running board and extends all the way to the back to accentuate the chrome rear bumper. The running boards and rear step bumper are equipped with skid-resistant surfaces for better footing. Design and functional features of the rear fascia include round backup lights and a weight distributing trailer hitch.
18-Inch Wheels and Tires
The Sierra Ace meets the road with 18-inch chrome-plated, cast-aluminum, six spoke wheels and custom-designed 285/60R18 Michelin tires.
Unique Cargo Space
Among the unexpected functional features is the cargo bed arrangement. Flanked by chrome rails, the cargo box has three separate compartments and a hard tonneau cover.
Body-Colored Sail Fin
Cab styling includes a body-color wide sail fin with integrated CHMSL for rear illumination excellence. Additionally, the harmonious flow exterior sheet metal is preserved by the placement of the third door handle inside the shutface of the passenger side door. For the convenience of rear seat occupants, the third door has an interior release latch.
Striking Interior Design
Interior appointments are designed for functional as well as occupant comfort and striking design. To arrive at the best possible driver and passenger environment, engineers applied the Human Factors Criteria Index in designing such functional features as control accessibility, entry and exit, instrument cluster displays and storage space.
Logical, User-Friendly Instrument Cluster
The result is a logical, user-friendly instrument cluster that offers a reconfigurable telltale to monitor 19 functions, an electronic odometer with trip meter, an engine hour meter and a transmission temperature gauge. Additionally, the ACE's instrument panel contains cupholders to accommodate various size containers and two covered power points as well as a lighter.
Rear Seat HVAC
The HVAC system has easy-to-use- controls as well as unexpected features such as rear seat heat and air-conditioning ducts and air filtration.
A wood-accented center console includes provisions for a cellular phone and a flip down extension that can accommodate dual playback systems or additional stowage.
Benchmark Seating
But among the most unexpected of all interior amenities is the design and construction of the seats. The seats are the only part of the vehicle that the customer touches at all times when inside the truck. For that reason, the Sierra ACE seats were designed to be the benchmark in comfort, durability and safety in the full-size pickup segment.
Front seat hip room is 1.3 inches wider than that of the current Sierra seats, and the front seat track is 34 percent longer to accommodate drivers of all sizes.
Easy Entry Rear Seat
The rear seat is easier to enter and exit and the seatback is angled 18 degrees for a more natural seating position. The rear seat bottom is two inches longer than that in the current extended cab Sierra. An extra convenience feature is the wood-accented rear-seat fold-down console with cupholders and storage.
Reliable Electrical System
Bussed Electrical Center (BEC) architecture provides unmatched versatility and reliability in the power and signal distribution system. BEC architecture centrally locates electrical system functions making them easier to use and service. Point-to-point wiring reduces power loss, minimizes wire gauge size and simplifies wire harness assembly. All this translates into improved reliability and durability for the customer.
Stronger Frame
The show truck's frame accommodates new dimensional specifications that improve ride quality and stability over the current generation Sierra. Wheelbase is extended by two inches, rear track is widened by 2.5 inches and front track in .9 inch wider than the current truck.
Structurally, the frame of the Sierra ACE is stronger and stiffer but lighter than the frame of today's Sierra pickup. Structural changes such as the use of hydroforming the front rail section improve sheet metal fit, dimensional control of brackets, crush performance and serviceability
While the current Sierra pickup is solid and well-built, the Sierra show truck takes structural integrity to a new level. Joints have been stiffened and section properties have been carefully tailored to optimize their structural performance. For example, the rocker section is 111 percent deeper. A-pillar to hinge-pillar stiffness is improved 193 percent and hinge-pillar to rocker joint stiffness is improved 194 percent.
Stiffness of the door frame section at step-in has increased by 249 percent, B-pillar section stiffness increased by 272 percent and C-pillar stiffness increased by 298 percent.
265-Horsepower Vortec 5300
Power for the Sierra ACE comes from the new generation Vortec 5.3 liter V8 engine that generates 265 horsepower at 5000 rpm and 320 lb-ft of torque at 2800 rpm. The 5300 engine was engineered to deliver maximum torque early in the torque curve for excellent launch power and to reach maximum horsepower at high rpms for sustained pulling and hauling power. The 5300 Vortec engine is mated to a four-speed, electronically controlled automatic transmission. The transmission includes a new torque converter that generates less heat than pervious torque converters.
Tow/Haul Mode
In order to provide world-class trailering capacity, the Sierra ACE offers Tow/Haul mode selection. When the vehicle is loaded, the driver can select Tow/Haul mode by pressing a button on the shifter. This modifies the transmission to make the shift firmer and to lengthen the time between shifts. Benefits include improved drivability in stop and go situations and fewer shifts in hilly terrain.
Autotrac
The Sierra ACE is equipped with GMC's AutoTrac active transfer case that automatically transfers power to the front axle when slippage occurs in the rear wheels. This system can transfer from 0 to 100 percent of power to the wheels with the most traction.
Four-Wheel Disc Brakes
Four-wheel disc brakes include larger rotors and pads and better ventilation for improved brake cooling. Additionally, brake pads are made of a noncorrosive organic material for enhanced durability.
"We have a great twentieth century truck in the current generation Sierra," said Kornas. "But the Sierra ACE hints at what GMC has in mind for a full-size pickup for the next century."
# # #
Contact:
Pontiac-GMC Communications
(313) 667-4000
FAX (313) 667-4001
Vortec 5300 V8 Powers GMC Sierra ACE Show Truck
DETROIT - The powerplant for the GMC Sierra ACE show vehicle sets a new standard for efficient V8 engines just as the complete truck sets new marks for the full-size pickup segment.
More Horsepower, Better Fuel Economy
Lighter than the current 5.7-liter V8, the Vortec 5300 5.3 liter V8 produces more horsepower and gets better fuel economy. While final EPA fuel economy numbers have not yet been established, engineers expect a noticeable improvement over the current 5.7-liter V8 truck engine.
A variant of the venerable small block General Motors V8, the Vortec 5300 generates 265 horsepower at 5000 rpm and 320 lb-ft torque at 2800 rpm. The 5300 engine was engineered to deliver maximum torque early in the torque curve for excellent launch power and to reach maximum horsepower at high rpms for sustained pulling and hauling power.
Long-term reliability and affordability are two traits truck owners look for in a powertrain. The new generation Vortec5300 V8 was designed to meet these needs with such features as a deep skirt block, two cross bolts per bearing cap, dual belt accessory drive and a hi-mounted generator to protect it from damage. The deep skirt design, in which the blok extends below the crankshaft centerline, increases block rigidity and resists torsional flex.
Pressurized Cooling System
A truck engine is only as good as its cooling system. The entire cooling system of the Vortec 5300 is pressurized, including the surge tank. This provides a more stable system with increased effective coolant capacity and still utilized long-life coolant that remains viable for 150,000 miles under normal conditions.
The cooling fan was developed from U.S. Navy submarine propulsion technology. The fan is one inch smaller in diameter than fans on current generation Vortec V8 engines but provides improved air flow and generates less noise. Additionally, a modulating fan clutch activates maximum air flow only when the cooling system needs to cool the engine. Otherwise, the clutch is disengaged and allows the fan to "free wheel" consuming minimum power.
Total coolant loss can be devastating for normal engines, but the Vortec 5300 has a coolant-loss protection system that allows the driver to continue on for a limited time to seek service.
Engine Feedback
The Sierra show truck is equipped with a number of monitors that give the driver immediate feedback about the engine. Key examples include an engine hour meter, an underhood air filter gauge, oil level and oil quality monitoring, transmission temperature gauge, and Driver Message Center in the instrument cluster. The DMC provides a series of warnings to let drivers know of potentially serious conditions.
4l60-E Transmission
The 5300 Vortec engine is mated to a four-speed, electronically controlled automatic transmission. While the 4L60-E automatic transmission has been serving Sierra trucks for several years, the show truck version includes a Tow/Haul mode, the transmission executes a more aggressive shift pattern-lengthening the time between gear shifts and making the shift itself much firmer. The Tow/Haul mode selector is a button on the shifter.
Other updates include a new torque converter that generates less heat than previously and a larger sump pump that delivers more fluid and therefore deduces heat in the transmission.
AutoTrac
The Sierra ACE is equipped with GMC's AutoTrac active transfer case that automatically transfers power to the front axle when slippage occurs in the rear wheels. This system can transfer from 9 to 100 percent of power to the wheels with the most traction.
Four-Wheel Disc Brakes
Four-wheel disc brakes include larger rotors and pads and better ventilation for improved brake cooling. Additionally, brakes pad are made of a noncorrosive organic material for enhance durability.
# # #
Contact: Pontiac-GMC Communications
(313) 667-4128
FAX (313) 667-4001
Sierra Ace Specifications
| Powertrain | Engine | Vortec 5300 V8 |
| Horsepower | 265 @ 5000 rpm | |
| Torque | 320 @ 2800 rpm | |
| Transmission | 4-speed automatic | |
| Specs and Dimensions (inches unless noted) | Length | 228 |
| Wheelbase | 119.5 | |
| Height | 65 | |
| Front Track | 65 | |
| Rear Track | 66 | |
| Ground Clearance (front/rear) | 11.4/12.6 | |
| Front Bumper to Back of Cab | 138.1 | |
| Head Room (front/rear) | 40.6/38.3 | |
| Leg Room(front/rear) | 41.3/33.2 | |
| Hip Room(front/rear) | 61.8/64/2 | |
| Shoulder Room(front/rear) | 65.2/67/6 | |