TM-9-2520-254-34 Direct Support for M113 TX100-1 Transmission 2520-00-066-4240 Download

to the reverse-range planetary carrier and rotates with it. Since the carrier is splined to the trans- mission output shaft, rear governor pressure is proportional to transmission output speed. The rear governor functions only during vehicle forward movement. Rear governor pressure is called G2 pressure. 2-8. Transmission Housing The transmission housing (31, fig. 2-1) is an alum inure casting. The one-piece housing is machined to provide a mounting which mates with either the engine flywheel housing or a mounting face on a transfer housing. It is open at the front and machined internally to receive all of the range gearing and clutches, and rear oil pump. Openings are provided at each side, with machined pads for mounting power takeoff units. The bottom of the housing is machined for the oil transfer plate and oil pan. 2-9. Oil Filter and Oil Pan a. Oil Filter Components (fig. 2-1). A pressed steel oil filter can assembly (55) is bolted beneath the valve body assembly (48). This assembly encloses a throw-away filter element assembly. Oil enters the can assembly through a horizontal pickup tube located near the bottom of the oil pan. Oil, after passing from the outside to the inside of the filter element, leaves the can assembly through tubes (4.5 and 57) leading to the front and rear oil pumps. The filter element is accessible from the left-front side of the oil pan. b. Transmission Oil Pan (fig. 2-1). The oil pan (42) is pressed steel and serves as the transmission oil sump. It is attached to the bottom of the transmission housing by 26 bolts which pass through a flared rim. The oil pane encloses an oil filter (55) and can, control valve assembly (48), and oil transfer plate (50). Fittings are provided for the oil filler, drain plug, and for retaining the oil filter element. 2-10. Transmission Shafts a. Converter Turbine Shaft (fig. 2-1). The transmission has two shafts which transmit all torque. The turbine shaft (59) is the longer shaft. It is splined at both ends and has drilled passages. The front passage directs lockup pressure to the lockup clutch. The rear passage carries lubricating oil. The converter turbine (6) is splined to the front of the shaft. The high-range clutch housing (16), intermediate-range sun gear (53), and the low- range sun gear (46) are splined to the rear. The turbine shaft transmits torque from the turbine to the range-gear section of the transmission. b. output Shaft (fig. 2-1). The transmission output shaft (33) is an integral part of the low- range planetary carrier and output shaft assembly. The carrier is the large, front portion of the assembly. The shaft is splined for approximately one half its length at the rear. The reverse-range planetary carrier assembly (37), speedometer drive g-ear (34), and the output drive flange (35) are splined to the shaft. A bushing at the front supports the rear of the turbine shaft (59). 2-11. Oil Transfer Plate, Valve Body, and Controls a. Oil Transfer Plate (fig. 2-1). A cast aluminum plate (50), bolted to the bottom of the transmission housing (31), provides a mounting for the control valve body assembly (48). Holes and passages in the transfer plate route oil flow and pressure between the transmission housing and various valves in the valve body. A secondary function of the oil transfer plate is the retention of the two range clutch anchor pins. b. Control Value Body Assembly (fig. 2-1). The control valve body assembly (48) is mounted on the oil transfer plate (50) within the oil pan (42). The assembly includes a system of valves and control devices, all of which operate automatically with the exception of the manual selector valve and throttle valve (TV). Pressure regulation, shifts between ranges, lockup control, and clutch apply regulation are the functions of this assembly. c. Manual Controls. The manual selector valve and throttle valve in the control valve body assembly are actuated by two lever and shaft assemblies. The levers are inside the oil pan area. The shafts are integral with the levers and extend through a single opening to the outside of the transmission housing at the left side. The selector valve shaft is the larger and is hollow. The small throttle valve (TV) shaft is solid, and passes through the hollow center of the selector valve shaft. Seal rings prevent oil leakage. Snap rings retain the shafts. Splines at the outer ends of the shafts provide points for attaching external control levers. d. operation of Value Body and Controls. Because of the importance and complexity of the valve body and controls, and their interrelation with other components of the transmission, a separate section in this chapter is devoted to the hydraulic system. Refer to paragraphs 2-12 through 2-21. 2-6