2009/07/20 Improved Sun Gears and Planetary Gears Are Now Used in the Second Reduction of the D11R and the D11T Final Drive {4050} Caterpillar

Track-Type Tractor:

D11R (S/N: AAF1-UP; 9TR1-UP; 9XR1-UP; 7PZ1-UP)

D11T (S/N: GEB1-UP; TPB1-UP)

Service Magazine SEPD1001, 20 July 2009, "Improved Sun Gears and Planetary Gears Are Now Used in the Second Reduction of the D11R and the D11T Final Drive". Disregard this article. See the article that follows. Two clarifications were made in this article. Some serial number effectivity was clarified and it was also clarified that four planetary gears are required for each sun gear that is replaced.

Description of Change: The durability of the D11R and the D11T final drive has been improved with the introduction of the new gears. A new sun gear and new planetary gear are now used for the second reduction of the final drive. The improvement comes as a result of isotropic finishing on the surface of the gear, which improves the life of the gears. The ring gear remains unchanged.

Adaptable To: The 207-6938 Sun Gear will be replaced with the 276-8185 Sun Gear. The new gear has an isotropic finish. The four 207-6939 Planetary Gears will be replaced with four 276-8186 Planetary Gears. Four planetary gears are required for each sun gear. The new gears have an isotropic finish. In order to get maximum benefits from this change, sun gears and planetary gears with the isotropic finish should not be mixed with sun gears and planetary gears that do not have the isotropic finish. The effectivity for these components is listed below in Table 1.

Table 1

Effectivity
Model	Adaptable To Machines	Effective With Machines
D11R	S/N:7PZ1,5019	S/N:7PZ5020-UP
D11R	S/N:9TR1-75004	S/N:9TR75005-UP
D11R CD	S/N:9XR1,75001	S/N:9XR75002-UP
D11R CD	S/N:AAF1-75003	S/N:AAF75004-UP
D11T	S/N:GEB1-490	S/N:GEB491-UP
D11T CD	S/N:TPB1-176	S/N:TPB177-UP