TM-9-2520-254-34 Direct Support for M113 TX100-1 Transmission 2520-00-066-4240 Download
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a. Inhibitor Prevents 2-1 Downshift at Excessive Speed (fig. 2-10). (1) Figure 2-10 illustrates the hydraulic System in intermediate-range operation even though the manual selector has been moved to a position which does not indicate intermediate-range operation. This condition results when vehicle (transmission output) speed is too great for safe operation in low range at the time a manual downshift is made. (2) When the manual downshift is made, rear governor (G2) pressure is sufficient to continue holding the low-intermediate shift plug, shift valve, and blocker plug upward against spring force and inhibitor pressure. This extends intermediate-range operation of the transmission during the period the vehicle is moving at excessive speed. (3) When vehicle speed decreases, G2 pressure also decreases. When G2 pressure falls to a value which will no longer hold the low-intermediate shift plug, valve, and blocker plug upward against spring force and inhibitor pressure, the downshift to low range will occur. This is an automatic shift, which lags behind the manual shift. b. Other Functions Same as Low-Range operation (fig. 2-10). In intermediate-range operation (selector at 1-position), the circuits not involved in action of the intermediate-low inhibitor operate as described in paragraph 2-15 for low- range operation. 2-25