GMC Terradyne - AllCarIndex

GMC Terradyne: Innovative Functionality

DETROIT - The name Terradyne comes from "terra," Latin for "of the earth," and the Greek "dyne," meaning "strength and power." It's a name that evokes an image of strong, dynamic capabilities. The Terradyne concept vehicle lives up to the name: With exciting innovations and an emphasis on industrial precision, Terradyne brings exciting new functionality to its role as a powerful tool with capabilities that exceed requirements.

Terradyne is a truck that "is good down to its bones." Under its tilt-forward full hood, the powerful new Duramax 6.6-liter V8 sets new standards for diesel power, performance, durability and quiet operation. The engine, which will be available as optional equipment on 2001 GMC Sierra 2500HD/3500 Series pickups, is a 90-degree, direct-injection, overhead valve (OHV), four-valve-per-cylinder, intercooled turbo-diesel V8.

The Duramax 6600™ engine offers excellent fuel economy through its lightweight design and a new direct-injection, common-rail fuel system, which provides maximum power for each pulse of fuel used. Like other direct injection systems, the Duramax 6600™ injector sprays fuel directly into the combustion chamber, producing more efficient combustion. Unlike other systems, injection pressure is independent of engine speed. Instead, fuel is computer-controlled by the Electronic Driver Unit (EDU), which works with the Engine Control Module (ECM) to adjust the fuel pressure. Variably controlled pressures of up to 23,000 psi -- up to three times higher than a normal fuel injection system -- deliver the most effective combustion for the engine's current operating conditions. This system lets the Duramax 6600Ô achieve excellent fuel economy while lowering emissions and enhancing performance over the entire engine speed range.

The sophistication and technology of the direct-injection system components also allow the Duramax 6600™ to use a process known as "pilot injection." A small amount of fuel is injected into the cylinder before the main injection occurs. This lets combustion start on a small scale and build rapidly, resulting in reduced engine knock, less vibration and quieter, smoother start-ups.

The Duramax 6600™ four-valve-per-cylinder configuration is state-of-the-art for modern diesel engine design. It optimizes airflow in and out of the engine, improves breathing at higher rpms, and processes more air. All that air results in more horsepower than competing designs. A slight twist to the shape of its valves gives incoming air added swirl, which improves the combustion process, controlling emissions and maximizing fuel efficiency.

A cooler-running engine runs more efficiently, is more reliable and puts more power at the driver's command. That's why there's no shortage of cooling capabilities built into the Duramax 6600™. A charge air cooler functions as an air/air radiator, taking compressed air from the turbocharger and cooling it. This cooler, denser air flows into the engine, where it improves fuel combustion to provide more power.

An integral oil cooler, like those found on many medium-duty truck engines, uses water from the gear-driven water pump to lower oil temperatures. A piston spray cooling system sprays oil directly onto each piston, helping to reduce operating temperatures. A transmission oil cooler, mounted below the radiator, allows the transmission to operate efficiently and extends the life of the components. A large, 21-inch-diameter composite fan features a large modulating clutch that reduces fan noise. All these features contribute to a cooler-running engine and transmission, enhancing the vehicle's reliability and the customer's peace of mind.

Torque is the force that lets a driver get their vehicle and load moving. The Duramax 6600™ engine delivers more torque across the power band than any competitor, helping Terradyne excel in off-the-line performance, acceleration and heavy-duty trailering and hauling. With a targeted operating life of at least 200,000 miles, the engine also delivers low maintenance costs and increased customer confidence. Key durability enhancements include a nitrided crankshaft -- nitriding creates a hard surface for excellent crankshaft bearing life. A deep-skirt block design and an exclusive induction hardened block offer excellent engine balance and a rigid structure, elements that provide smoother, quieter engine and driveline operation. Hardened valve seat inserts in the aluminum cylinder heads are another exclusive for engines in this class, providing improved durability and reliability.

The combination of these structural enhancements and the electrically-controlled fuel-injection system gives the Duramax 6600™ noise, vibration, and harshness (NVH) figures more typical of a similar-sized gasoline engine than a diesel engine. Easy serviceability is created by the engine's compact size, the placement of the turbocharger in the "V" space atop the engine, and the thoughtful placement of items such as the timing gear chain, oil filter and fuel filter. All are easily accessible and offer reduced service time.

Another of Terradyne's features helps users leverage the full power and torque of the Duramax 6600™ - the Allison Transmission 1000 SeriesTM 5-speed automatic transmission. In addition to handling the substantial power and torque of the Duramax 6600™, the 1000 Series delivers superior shift quality and best-in-class towing capability.

The 1000 Series is a fully automatic, 5-speed, electronically-controlled transmission with helical gearing that gives Terradyne a new level of performance and operational flexibility. A 12-inch torque converter with an electronically controlled, hydraulically actuated converter clutch delivers smooth shifts and good fuel economy.

The 5-speed configuration gives the driver excellent off-the-line performance and acceleration at lower speeds, as well as greater control on steep grades and during heavy-duty trailering and hauling. Five speeds give Terradyne a wider power band for more efficient power at any speed. The first four gears have closely spaced ratios, meaning better throttle response and acceleration to get the load moving. Fifth gear overdrive reduces engine rpm at higher speeds, so drivers experience excellent fuel economy and enhanced, quiet engine performance. The electronic controls provide superior smoothness and shifting consistency.

The transmission also gives Terradyne power-takeoff (PTO) capability - previously available only with a manual transmission on GMC pickup trucks. PTOs are commonly used to transfer engine power to an onboard hydraulic pump, powering dump truck bodies, hoist or drive generators or compressors.

The 1000 Series offers two modes of operation that let Terradyne operate equally well when loaded or unloaded. Normal mode, used during normal day-to-day driving, engages the converter clutch in fourth and fifth gear ranges for a superior combination of performance and shift quality. When hauling a heavy load, the driver can choose the Tow/Haul mode by pressing a button on the end of the gearshift lever. Tow/Haul mode holds gears longer, putting more torque where it's needed. Once the load is moving, Tow/Haul mode helps the driver haul heavy loads in overdrive for less noise and improved fuel economy. There's less hunting between gears when climbing hills, so the transmission stays cooler. Because the transmission builds more power for crisp shifts in Tow/Haul mode, drivers get the same solid shift feel whether they're traveling light, hauling cargo or towing a trailer.

Engine grade-braking, another new feature of Terradyne's transmission, helps the driver slow the vehicle and avoid excessive use of the brakes. For example, when drivers carrying heavy loads go down a steep hill without engine grade-braking, they can either use the brakes or manually shift into a lower gear to slow the truck. The 1000 Series uses operating data, such as how long the driver's foot has been on the brake, vehicle speed, and the gear currently engaged to calculate shift parameters. At a certain threshold, the driver can activate a brake-pedal command by tapping the brakes, and the transmission will downshift without the driver having to move the gear lever. Manual range selection always remains available to the driver.

Terradyne's 5000 watt on-board, engine-driven generator provides unprecedented functionality and versatility. At work on the jobsite, the generator can use the 110V and 220V outlets located in the tailgate area to run tools and machinery, making a portable generator or other power source unnecessary. This "power on site" can also make family recreational activities much more enjoyable, allowing users to take the conveniences of home with them wherever they go.

With Terradyne, GMC also introduces QuadraSteer™ -- a remarkable four-wheel steering system. This innovation provides the agility of a smaller truck or car, allowing the driver to turn tightly at low speeds. The system also enhances stability at highway speeds, compensating for factors such as the wind turbulence encountered when the vehicle is passed by a large truck. The additional stability and control also enhance Terradyne's towing capabilities both at high and low speeds.

Terradyne exceptional functionality is the result of GMC's 98 years of state-of-the-art truck building expertise. It's a truck with the characteristics of a well-made precision tool: thoughtfully designed and engineered, easy to use, and a solid feel matched with outstanding levels of capability.

source: GMC

Engine & performance:

Position:

Type: Duramax 6600™ (6.6 liter) turbo-diesel

Capacity: 6.6-liter

Power: 300 hp @4200rpm

Torque: 705 hp @ 1800 rpm

Drive: 4WD

Dimensions:

Length: 5723 mm

Width: 2057 mm

Height: 2047 mm