Allison Transmission

Allison began in 1909 when James A. Allison, along with three business partners, helped fund and build the Indianapolis Motor Speedway. In 1911, Allison's new track held the first Indianapolis 500 mile race. In addition to funding several race teams, James Allison founded the Speedway Racing Team Company on September 14, 1915[4] and quickly gained a reputation for his work on race cars and automotive technology in general.[5] Allison built a shop near the track and changed the team's name to the Allison Experimental Company; the shop later became Plant No. 1.[4]

When World War I began, Allison suspended racing, and the Allison Experimental Company began machining parts, tools, and masters for the Liberty airplane engine — the main power plant used in the US war effort. After the war, Allison entered a car in the 1919 Indy 500 and won. It was the last race Allison's team ever entered as he turned his company's attention to aviation engineering, renaming it to Allison Engineering Company; the aviation-focused company developed steel-backed bronze sleeve bearings for the crankshaft and connecting rods, and high-speed reduction gearing to turn propellers and Roots-type blowers.[4] The company's reputation and expertise in aviation was the major factor in General Motors decision to buy the company following James Allison's death in 1928.[6][7]

Allison V-1710

Shortly after the sale to General Motors on April 1, 1929, Allison engineers began work on a 12-cylinder engine to replace the aging Liberty engines. The result was the V1710 12-cylinder aircraft engine and it made the company, renamed to the Allison Division of GM in 1934,[4] also known as the Allison Engine Company, a major force in aviation.[8] Plant 3 was built in 1939, a 360,000 sq ft (33,000 m²) factory to build V1710 engines. Due to demand during World War II, Allison would add a second factory (Plant 5) and 23,000 new employees; by the end of the war, Allison had built 70,000 V1710 engines.[4]

Alongside the development and production of the V1710, engineers at GM began designing the CD-850 cross-drive steering transmission for tracked military vehicles in 1941; the design was completed in 1944 and Allison was awarded the contract to manufacture the prototypes. In February 1945, General Motors formed the Allison Transmission Engineering Section, dividing the subsidiary into Aircraft Operations and Transmission Operations in 1946.[4] The CD-850 combined range change, steering and braking.[9][10] Allison stopped producing the CD-850 in 1986, but a licensed version was produced in Spain for more than a decade afterward.[4]

General Motors began developing automatic transmissions with a hydraulic torque converter in the 1930s under its Product Study Group, offering it as an option for Oldsmobile for the first time in 1940.[4] After World War II, Allison Transmission turned its attention to civilian transportation. Allison designed, developed and manufactured the first-ever automatic transmissions for heavy-duty vehicles including delivery trucks, city buses, and locomotives, starting from 1948.[9][10] In addition, Allison marketed transmissions for off-highway heavy-duty vehicles under the brand Powershift TORQMATIC, with the first TG series transmissions being produced in July 1948.[11]

At approximately the same time the CD-850 was going into production, GMC Truck and Coach Division requested that GM develop a V-Drive transmission with a torque converter in 1945 for transit bus use, replacing the Spicer manual transmission then offered.[4] These buses had rear-mounted engines and to maximize passenger space, the engine compartment was minimized; the V-Drive transmission was named for the 63° angle of intersection between the transmission shaft input (from the engine) and output (to the rear axle).[4] Development of the V-Drive transmission was led by Bob Schaefer, an emigrant from Germany who had joined GM in 1942 after helping to lead the Twin Disc Company, which was one of the licensees of the Ljungstroms hydraulic torque converter. Schaefer was reassigned from the Detroit Transmission Division to Allison in 1946.[4]

Detroit Diesel 6V71 with Allison V-Drive transmission in an AC Transit GM New Look bus

The first production V-Drive transmissions were delivered in October 1947, with the first major contract being for 900 buses in 1948, for New York City.[4] The VS-2 was introduced in 1955, which added a two-speed input splitter; a version with both hydraulic and direct clutches was introduced in 1958 (VH), and production of the original V-Drive transmissions was concluded in July 1976, with 65,389 produced.[4]

In addition to the transit bus market, Allison began developing automatic transmissions for commercial trucks in 1953. This effort resulted in the MT-25, which designated the intended application ("M"edium "T"rucks) and maximum input power, 250 hp (190 kW). The MT-25 was a 6-speed automatic, using a two-speed high/low splitter and three-speed double planetary gear train. The splitter was equipped with a hydraulic retarder.[4] Because of the additional cost of the automatic transmission, sales were initially slow until Allison began targeting specific markets that required both on- and off-road driving as well as frequent stops and starts, such as concrete mixing and garbage trucks in the early 1960s.[4] The MT-25 was fitted first as an option branded POWERMATIC by Chevrolet,[12][13] exclusive to that brand for the first year, but was soon offered by other truck manufacturers including Ford (1957), Reo (1958), Dodge (1958), Diamond T (1959), White (1961), and International Harvester (1961); production of the MT-25 continued into the early 1970s.[4]

The MT-25 was supplemented in September 1970 by a second-generation lighter-duty automatic transmission, the four-speed AT-540,[14] which Allison developed jointly with Hydramatic Division in the late 1960s; the AT-540 was targeted specifically for on-highway use and shared similarities with automobile transmissions to reduce the cost penalty to equip on-highway trucks with automatic transmissions.[4] Later, the MT-25 itself was replaced by the MT-640 and a heavier-duty version, the HT-740, was introduced; the new MT and HT were both derived from the AT-540. As an option, the MT-6nn and HT-7nn series transmissions could be equipped with a lower fifth gear for severe off-road conditions.[4] In 1970, GM combined the Allison and Detroit Diesel divisions as the Detroit Diesel Allison Division of GM.[4]

The 500-series transmissions (AT-540, etc.) were rated to accept input power of up to 235 hp (175 kW) and were intended for vehicles up to 30,000 lb (14,000 kg) gross vehicle weight (GVW). The medium-duty 600-series had increased ratings to 300 hp (220 kW) and 73,280 lb (33,240 kg) GVW, while the heavy-duty 700-series were rated to 445 hp (332 kW) and 80,000 lb (36,000 kg) GVW.[4] In 1976, a 700-series V-Drive transmission was introduced for buses, the V730.[4] The AT/MT/HT were still being produced in 1998.[4]

Allison also produced off-highway transmissions in the 1960s, starting with the "Dual Path Powershift" DP 8000 series.[15] The first electronic controls were fitted to the off-highway DP 8000 series transmission in 1971.[16] Electronic controls (branded the Allison Transmission Electronic Control or ATEC system) were added to the MT/HT/V730 in 1983, improving fuel economy by more precisely controlling shifts.[4]

Cutaway view of 3rd-gen (WT) MD3060

The third-generation six-speed World Transmission (WT) was introduced in 1991, replacing the second-generation AT/MT/HT/V730 lines. Development of the WT had begun in the mid-1980s, prior to the sale of Detroit Diesel to Roger Penske in 1987. The WT used the WT electronic control (WTEC) system to control the internal clutches during shifting, equipped with a control unit that adapts to variations during use.[4] The WT line was split into MD (medium duty), HD (heavy duty, introduced in 1993),[17] and B (T-drive buses) lines;[4] the MD and HD lines were later renamed to the 3000 and 4000 Series, respectively.

As of 1998 in the United States, Allison had built 92% of the transmissions in school buses; 75% of transit bus transmissions, 65% of heavy-duty garbage truck transmissions, and 32% of all medium-duty truck transmissions.[4]

Allison followed the WT (3000 and 4000 Series) line with the 1000 and 2000 Series starting in 1999.[4] The 1000 Series transmission incorporated many features from the WT line for light-duty trucks, including the electronic control system, and was initially available as an option with the 6.6L GM/Isuzu Duramax diesel engine for the trucks based on the GMT800 platform.[18]

In 2007, GM sold Allison Transmission to private equity firms Carlyle Group and Onex Corporation for US$5.6 billion.[19]

• 1949—Allison begins production of CD-850 tank transmission, division's most historically significant transmission[9]
• December 1949—First rail car transmission is produced; installed in the Budd Rail Car[11]

• 1954—First off-highway transmissions (CRT-5530/CRT-3330)[11]
• 1955—Allison develops the MT-25/POWERMATIC transmission for on-highway use with Chevrolet[11]

• October 1960—First Allison XT-1410-2 transmission is produced[20]
• June 1961—Allison announces MT Series transmissions
• July 1962—Allison TT-2000 Hydro Powershift transmission is introduced
• March 1965—Introduction of dual path DP-8000, largest single-package Allison Powershift transmission to date[11]
• November 1966—Lithium-chlorine fuel cell is unveiled
• June 1967—Allison begins production of new DP-8960 for large off-highway trucks[11]
• October 1967—First prototype of the Allison-equipped U.S. Army main battle tank is unveiled in Washington, D.C.[21][22]
• February 1969—Allison introduces electric gearshift control system for off-highway vehicles
• July 1969—Apollo 11 astronauts make man's first landing on the moon; propellant tanks built by Allison are part of the Service Module[23]

• September 1970—Merge with Detroit Diesel Engine to form Detroit Diesel Allison Division, headquarters in Detroit
• January 1971—Allison introduces first 4-speed automatic transmission for 72,000 lb (33,000 kg). GVW highway vehicles; Allison model HT-740[24]
• April 1973—First fully automatic transmission for large trucks, scrapers and other types of heavy-duty off-highway vehicles is introduced; Allison model CLBT 750[25]
• 1974—First European office is established

• October 1982—A new generation heavy-duty automatic transmission, the Allison DP 8962, is announced; incorporates over 15 new technology internal changes
• May 1983—GM sells Allison Gas Turbine Division; Allison becomes part of newly formed GM Power Products and Defense Operations Group[26]
• June 1986—First X200 military transmission is released[27]
• December 1987—Detroit Diesel Allison becomes Allison Transmission, Division of General Motors

• February 1991—Allison introduces electronically controlled World Transmissions[28]
• November 1995—Allison adopts lean manufacturing principles and begins implementing Allison Production System (APS), a cellular manufacturing system; some 10,000 machines and support equipment are re-arranged through all plants
• 1999--Hybrid bus program is demonstrated for New York City Transit Authority
• June 1999—Allison introduces 1000 Series and 2000 Series fully automatic transmissions

• 2000--Hybrid electric program is launched
• September 2000—Test Track 2000 is first customer ride and drive simulating real-world operating conditions; held at Walt Disney World in Orlando, Florida
• January 2001—Allison unveils first-of-its-kind parallel hybrid technology
• November 2003—Allison's Ultimate Truck Driving Adventure takes ride and drive experience to extremes in the high desert of Nevada
• November 2003—Allison Vocational Models are released to better serve specific applications
• May 2005--Shanghai Customization Center is opened
• June 2007—GM announced that it was selling Allison Transmission to private equity firms The Carlyle Group and Onex Corporation, in a deal valued at $5.6 billion.[19] The transaction closed on August 7, 2007.
• 2008—Allison introduces on-board prognostics on model-year 2009 automatic transmissions
• 2009—Allison took an approximately 10% stake in UK-based Torotrak[29] manufacturer of Infinitely Variable Transmission (IVT).

• 2010-Manufacturing plant opened in Chennai, India also establishing regional headquarters with executive, marketing and sales offices
• June 2010-Allison dedicates a new hybrid manufacturing plant in Indianapolis, Indiana.[30]

• March 15, 2012 Initial public offering of 26.3 million shares of Allison Transmission stock at $23/share on the New York Stock Exchange under the symbol ALSN.[31]
• October 27, 2013 Allison 10-speed TC10 transmission available for order at Navistar[32][33]
• Current revenues were at $1.985 Billion a decrease from 2014.[34]

Allison Transmission vocational series and family availability overview[35]

Vocational series (model designation)	Transmission family
	1000	2000	3000	4000	5000	6000	8000	9000	TC10
Highway (nnnn HS)
Motorhome (nnnn MH)
Bus (B nnn)
Emergency Vehicle (nnnn EVS)
Rugged Duty (nnnn RDS)
Pupil Transport/ Shuttle (nnnn PTS)
Truck RV (nnnn TRV)
Specialty (nnnn SP)
Oil Field (nnnn OFS)
Off Road (nnnn ORS)
Tractor (TC10 TS nnnn)

Notes

The model designations for off-highway transmissions marketed under the Powershift TORQMATIC brand were in the format AAAA 1234, where:

For example, the TT 2220 was a twin-turbine 2000 series automatic transmission with two forward speeds and a maximum input torque capacity of 250 lb⋅ft (340 N⋅m).[37][38]

• First Generation
  • Allison V transmission—VH, VH2, VH4, VH5, VH6, VH7, VH9, VS1, VS2-6, VS2-8
  • Allison MT transmission—MT25, MT30, MT31, MT40, MT41, MT42[37][39]
  • Allison HT transmission—HT70[37]
• Second Generation
  • Allison M and MH marine reverse and reduction gear
  • Allison AT transmission—AT540, AT542, AT543, AT545 (4 speeds)
  • Allison MT transmission—MT640, MT643, MT644, MT647, MT648, MT650, MT653DR, MT654CR, MTB643, MTB644, MTB647, MTB648, MTB653DR, MTB654CR
  • Allison HT transmission—HT740D, HT740RS, HT741, HT746, HT747, HT748, HTB748, HT750CRD, HT750DRD, HT754CRD, HT755CRD, HT755DRD, HTB755CRD, HTB755DRD
  • Allison V transmission—V730, V731, VR731, VR731RH
• Third Generation
  • Allison World Transmission (MD and HD)—MD3060, MD3060P, MD3560, MD3560P, MD3066, MD3066P, HD4060, HD4060P, HD4560, HD4560P

• Hybrid buses will save an estimated 2.4 million US gallons (9,100 m³) of fuel annually in Washington D.C., Philadelphia and Minneapolis/St. Paul
• Low-Emissions Hybrid Buses.