New Allison automatics
Page 36
If you've noticed an error in this article please click here to report it so we can fix it.
• An all-new automatic transmission aVailable in two versions—one for gas turbine engines and one for diesels—has been introduced by the Detroit Diesel Allison Division of General Motors Corporation.
Called the HT 740, the four-speed automatic transmission is designed for turbines and diesels of from 250 to 400hp.
The transmission is the second in a new family of Allison automatics and will be available to vehicle manufacturers in July, 1971.
The HT 740 is designed for onand off-highway vehicles of from 72,000 to 130,000lb. This includes a growing number of vehicles for which there has never been an automatic available until now.
In late 1969, Detroit Diesel Allison introduced the first member of its, new transmission family—the AT 540—a four-speed automatic for vehicles of from 10,000 to 33,000lb gvw.
The latest diesel version includes an integral hydraulic torque converter and as complete transmission assembly weigh; 8001b. This is a weight reduction of near13 20 per cent from an earlier Allisor automatic for vehicles of similar weight. Tly turbine model, which weighs 6001b, has n( converter and is. coupled directly to ttu engine.
The HT 740 features compact planetar3 gearing providing four speeds forward an one in reverse With maximum torqm coverage of 8.1 -to one. Individual gea ratios are: 3.69:1 in first gear, 2.07:1 ii second, 1.40:1 in third and 1.99:1 in fourth Reverse is 5.73:1.