The SSL travel drive motors are radial piston motors with a similar type of design as the "B"
Series machines. The brakes are spring engaged and hydraulically released. The MTL drive
motors are axial piston motors
Each hydrostatic drive motor contains a flushing valve. The flushing valve maintains a
minimum system pressure as it drains some oil from the low pressure side of the drive loop.
The pump crossover relief valves helps supply the makeup oil that the flushing valve drains.
As the oil flows to the case drain, heat and any contamination is purged from the drive loop.
The "C" Series travel motors each contain a speed sensor (1) that send a speed signal to the
Machine ECM indicating motor speed and direction.
A two-speed travel system is optional on all machines. The SSL two-speed travel motor
contains additional spools and passages which forces the motor to spin faster for the same flow
rate to control flow from the pump. The MTL two-speed travel motors utilize a swashplate to
control the flow to achieve the same end result.
A two-speed solenoid is mounted below the hydrostatic drive pump. The two-speed solenoid
valve is used to shift the travel motor control spool.
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SERV1833-01 - 53 - Text Reference
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