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Everything You Wanted to Know About Allison Transmission

Inside of Allison Transmission

Everything You Wanted to Know About Allison Transmission

Dating back to the early days of automotive engineering, Allison Transmission was created in 1915. However, the company’s origins began earlier when founder James Asbury Allison and a few friends established the Indianapolis Motor Speedway in 1909, helping cement this raceway into car history. With the outbreak of World War I, Allison shifted production from automotive and racing components to aviation parts and tools.

Following Allison’s untimely death in 1928, General Motors acquired Allison Transmission in a partnership that would last almost eighty years. In 2007, a cash-starved GM sold Allison to Onex Corporation and The Carlyle Group for $5.6 billion, a move that preceded GM’s bankruptcy reorganization in 2009.

A Century of Allison Transmissions

While not as glamorous as public-facing automobile production, transmission manufacturing is often the unsung hero of the car world. For more than 100 years , Allison has soldiered on with a continuous stream of advancement and innovation. As far back as 1966, the company developed a hybrid electric powertrain decades before most major automakers even considered such technology.

The effort made a now-proven case that a combination of electricity and an internal combustion engine can be an efficient power source. Other developments include a lithium-chlorine fuel cell used in an all-electric or hybrid electric vehicle setup.

By the late 1990s, Allison’s research and development with bus-based hybrids began to pay off as cities and bus manufacturers sought more efficient and less-polluting transportation systems. Allison is a pioneer in parallel hybrid technology that enables an internal combustion engine and an electric motor to propel wheels simultaneously. A common thing today, but a breakthrough twenty years ago.

Another Allison innovation was developing the first four-speed automatic capable of handling a 72,000 lb tow load in heavy equipment like bulldozers. However, among truck enthusiasts, Allison is best known for its venerable 1000 transmission. While there’s nothing overly exceptional about an Allison 1000 transmission, the gearbox has a longstanding reputation for reliability and continuous improvement.

One of the first uses of the five-speed 1000 transmission was its pairing with GM’s Duramax 6.6-liter V-8 Diesel engine. Engine output provided 520 lb-ft of torque, more than enough for the Allison transmission that’s rated for up to 620 lb-ft of torque. Current versions of the 1000 gearbox can handle up to 910 lb-ft of torque. In 2006, Allison introduced a double overdrive set up (a sixth gear) for 1000 for smoother highway driving and better fuel economy.

You’ll see the 1000 transmission in use with GM products ranging from Chevrolet Silverado pickups to GMC Kodiak work trucks. In general, an Allison 1000 transmission can manage power in vehicles up to a class 3 or 14,000 lb gross vehicle weight rating (GVWR). Variations of 1000 can be found in larger trucks. For example, the Allison 2000 can handle medium-duty trucks up to class 6 (26,000 lbs GVWR), while the 3070 and 4070 are used in class 8 trucks (big rigs over 33,001 lbs GVWR). Allison transmissions appear almost everywhere, from the original Hummer H1 military vehicle to the Chevrolet B-series line of school buses. One common combination is the pairing of the Allison 10L1000 transmission with the Duramax 6.6-liter V-8 turbo diesel in Chevrolet 2500HD/3500HD series of medium-duty trucks.

In the latest transmission development, the Allison te n -speed automatic now offered by General Motors is actually manufactured by GM. Allison is only a design and development partner for the project.

GM’s Silverado HD/Sierra HD Line of Trucks

Whether you choose the more popular Chevrolet Silverado HD flavor of GM heavy-duty trucks or are content with its upscale sibling, the GMC Sierra HD, these competent vehicles check all the boxes for refined ruggedness and extreme hauling capabilities. As many of these models rely on an Allison transmission, let’s explore a brief overview of these tremendous trucks .

We’ll focus on recent Chevy 2500HD versions for simplicity, but keep in mind that the nearly identical GMC 2500HD models may have slight variations in equipment and capabilities. Further, 3500 HD models will offer similar equipment and options but with different hauling capacities. For example, a 2018 Silverado 2500HD with the Duramax turbo-diesel can tow up to 18,1000 lbs, while a 2018 Silverado 3500HD with the same engine can handle up to 23,300 lbs. If over-to-the-top towing is in your future, or you prefer a dual-rear-wheel setup, then look more closely at the 3500HD line.

Note that the features in the various trim levels may vary from year to year.

Chevrolet Silverado 2500HD (2nd Generation): 2007-2014

a grey truck parked in a parking lot

An all-new Silverado HD ¾-ton full-size pickup launched for 2007 focused on refinement and significantly improved cabin quality. Available in regular cab, extended cab, and crew cab, the 2500HD could be equipped with a long bed or a standard bed (for extended and crew cab bodies). Standard power comes from the gas-powered 6.0-liter V-8 paired with a six-speed automatic and makes up to 360 hp and 380 lb-ft of torque (depending on model year). The optional Duramax 6.6-liter turbodiesel offered up to 397 hp and 765 lb-ft of torque. Later years of the 2500HD offered a bi-fuel option of gasoline or compressed natural gas (CNG) for the base engine. Rear-wheel drive (RWD) is standard, with all-wheel drive (AWD) as an option.

Trims begin with the starter Work Truck (WT) model that includes air conditioning (except for the regular cab version), OnStar telematics, and vinyl seating. Step up to the 1LT trim for extras like tinted windows, alloy wheels, CD player, keyless entry, and cloth upholstery. In 2LT form, the 2500HD includes front bucket seats, dual-zone automatic climate control, and steering-wheel audio controls. Leather seating, Bose sound system, and keyless/start are part of the upscale LTZ edition.

Chevrolet Silverado 2500HD (3rd Generation): 2015-2019

2015 Chevrolet Silverado parked on the hill

With similar configurations to the previous generation, the third-gen Silverado 2500HD could be built as a regular cab (with only the long bed) or as a double cab or crew cab (with either regular or long bed). Again, RWD is standard, and AWD is optional. The gas-powered 6.0-liter V-8 with a six-speed automatic carries over unchanged (included with the CNG option). Meanwhile, the optional Duramax turbodiesel can now make up to 445 hp and 910 lb-ft of torque (depending on the year). The accompanying Allison transmission also gets upgraded to handle the extra power.

The Silverado 2500HD starts with the WT trim and 17-inch steel wheels, rubber flooring, vinyl seating, air conditioning, power locks, and manual windows. However, despite its plain-jane status, the WT trim includes MyLink infotainment systems with Apple CarPlay and Android Auto, Bluetooth, and a six-speaker audio system. A 4G LTE WiFi hotspot is optional.

A single LT trim offers upgraded infotainment features along with full power accessories and a remote locking tailgate. The LTZ edition includes 18-inch allows and more creature comforts like leather seating, dual-zone climate control, power front seats with heat, driver seat memory, and a wiring harness with trailer brake control. Finally, a top-tier High Country trim offers goodies once available only on luxury SUVs such as upgraded leather seating, navigation, Bose audio system, 20-inch unique wheels, and advanced driver aids.

Chevrolet Silverado 2500HD (4th Generation): 2020-Current

2020 Chevrolet Silverado HD parked on the road

For 2020, the all-new Silverado 2500HD embraces a blunt front end and other standout design features. This is a truck that will not go unnoticed. Three cab configurations continue regular, double cab, and crew cab. Standard power comes from a new gas 6.6-liter V-8 paired with a six-speed automatic and makes 401 hp and 464 lb-ft of torque. The Duramax diesel (with 445 hp and 910 lb-ft of torque) and the Allison ten-speed automatic transmission continue as an option.

The base Work Truck (WT) model starts the Silverado 2500HD trim levels, and a new Custom model goes beyond the WT’s basics with larger wheels, power cabin accessories, and cruise control. The LT trim includes cloth upholstery, heated and power-adjustable mirrors, and a remote locking tailgate.

As with the previous generation, the higher-end LTZ offers leather seating, dual-zone climate control, power front seats with heat, an upgraded infotainment system, and a wiring harness with trailer brake control. The top-of-the-line High Country model continues with luxury features such as upgraded leather seating, ventilated front seat, and a Bose audio system.

Discover our selection of Used Chevrolet Silverado 2500HD, Silverado 3500HD, GMC Sierra 2500HD, and Sierra 3500HD trucks for sale Please note that our inventory changes frequently and is subject to prior sale. Be sure to ask us about incoming used Chevrolet Silverado and GMC Sierra models.

Buy a Used Chevrolet Silverado and GMC Sierra at Trust Auto

Truck buyers know how easily used Chevy Silverado and GMC Sierra shopping is at Trust Auto .

From our great selection of Silverado 1500, Silverado 2500HD, Silverado 3500HD, Sierra 2500HD, and Sierra 3500HD models to our truck-focused staff, Trust Auto in Maryland is the trusted choice for truck shoppers.

Buying a used truck in Maryland? Buying a used pickup in Pennsylvania? Then the best-used vehicles are just a short drive away. Buying a used truck in Delaware? Then learn how our remote shopping services can help you find the perfect vehicle without ever leaving home.

When your search calls for the best used car dealership near me, Trust Auto is the answer. From Baltimore and beyond, we’re the used truck dealer that’s all about you. Call or stop by today to explore our extensive selection of high-quality vehicles.


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