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Fuller Transmission Specs

by Karen Adams

Fuller transmissions, products of Eaton Corporation, provide power and quality for almost all heavy-duty vehicles. With several different types of speeds, from 5- to 18-speed transmission types, Eaton Fuller transmissions are continuously upgraded to distinguish them as industry standouts.

Transmission Types

Eaton Fuller makes more than 260 types of transmissions. These are separated into 5-speed, 6-speed,7-speed, 9-speed, 10-speed, 11-speed, 13-speed, 15-speed and 18-speed transmissions. They are broken down into different model types.

Heavy-Duty Model Classification

Fuller designates transmissions by a code that contains letters and numbers. The letters in the code mean different model types. FR stands for Fuller Roadranger, R stands for Roadranger, T for Twin Countershaft, L for Low-Inertia Concept, O for Overdrive and X for Overdrive. The first character in every model number is T, for Twin Countershaft. The second and third digits stand for 100 nominal torque capacity. The fourth digit states the model's design level. The fifth and sixth digits are forward speeds, and the last letter is the ratio set. For example, RTLOC-16918B translates to a Roadranger Twin Countershaft, Low-Inertia Concept, Overdrive Convertible with 16 x 100 nominal torque capacity, 9th design level, 18 forward speeds and B for ratio set.

5-Speed Transmissions

Overall, there are 23 -speed transmission types, separated into medium- and heavy-duty models. Medium-duty models are classified with the following formula: The first and second characters, or FS, mean Fuller Synchronized. The first digit is for 100 nominal torque capacity. The second digit stands for design level. The third and fourth digits stand for forward speeds and the final character is the ratio set. The medium duty models are as follows: FS-4205A, FS-4205B, FS-5005A, FS-5005C, FS-5005B, FS-5205A, FS-5205B, FS-6105A, FS-6105B, FS-6205A, GS-6205B, FS-6305A and FS-6305B. Heavy-duty models for 5-speed transmissions are T-11605A, TO-11605A, T-11605B, TO-11605B, T-11605C, TO-11605C, T-11605D, TO-11605D, T-11605F and T-11605M.

6- and 7-Speed Transmissions

There are 23 models of 6- and 7-speed transmissions. The 6-speed models are: F-6406A-ASW, FS-5106A, FS-5306A, FS-5406A, B-5406B, FS-6206A, FS-6306A, FS-6406A, FSB-6406B, FO-6406A-ASX, FO-8406A-ASX, FO-6406A-ASW, FSO-6406A, FSO-8406A, FS-7206A, FS-8206A and FS-8306A. The 7-speed transmission models include: T-14607A, T-14607B, TO-11607B-ASX, TO-14607B-ASX, TX-14607A and TX-14607B.

9-Speed Transmissions

This is the second most popular transmission type for diesel trucks after 10-speed transmissions. These models are as follows: RT-6609A, RT 8608L, RT-8609A, RT-8609L, RT-8709B, RT-8908L, RT-11609A, RT-11709H, RT-12609A, RT-12709H, RT-13609A, RT-13709H, RT-14609A, RT-14709H, RTO-11109B-ATE, RTO-13109B-ATE, RTO-14109B-ATE, RTO-16109B-ATE, RTOC-16909A, RTLOC-16909A-T2, RTOC-18609A, RTLOC-18909A-T2, RTX-11609B, RTX-11609R, RTX-11709H, RTX-12609B, RTX-12609R, RTX-12709H, RTX-13609B, RTX-13609R, RTX-13709H, RTX-14609B, RTX-14609R, RTX-14709H, RTX-16709B and RTX-16709H.

10-Speed Transmissions

The most popular type of Fuller transmission is the Ultrashift 10-speed. Unveiled in 2003 by Eaton, the Fuller 10-speed is an automated transmission type targeted for truck fleets in North America. There are 117 models for 10-speed transmissions with 12 different model series: the FM, FR, FRM, FRLO, FRO, RT, RTAO, RTL, RTLO, RTO, RTOM and RTX. See Resources for a full list of the 117 model types.

Other Transmissions

There are seven models of 11-speed transmissions and 15-speed transmissions, 16 models of 13-speed transmissions and 26 models of 18-speed transmissions. The 13- and 18-type models break down into UltraShift LEP, Super 13 or 18 Top and UltraShift LHP. See Resources for a list of these models.

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