TRACK LINK ASSEM. 8S2607 - Caterpillar

Transmission Clutch
Illustration 1 g00021395
Solenoid Valve (Transmission Clutch) The clutch solenoid valves for the transmission are outputs of the power train ECM. The power train ECM activates the appropriate clutch solenoid valves for the transmission. Clutch solenoid valves "1" and "2" are for direction. Clutch solenoid valves "3", "4", and "5" are for speed. For the movement of the machine, two clutch solenoid valves are activated. One clutch solenoid valve is for direction and one clutch solenoid valve is for speed. When the transmission is in neutral, only clutch solenoid valve "3" is activated. See table 1 for the status of the solenoid valves during shifting. When the transmission is neutralized, the solenoid valve for direction is deactivated and only the solenoid valve for present speed is activated. A solenoid valve is energized by a PWM signal that is sent by the power train ECM.
Table 1
Status of the Clutch Solenoid Valves    
Speed    Direction    Activated Solenoids    
First Gear     Forward     5 and 2    
Second Gear     Forward     4 and 2    
Third Gear     Forward     3 and 2    
Neutral     Neutral     3    
First Gear     Reverse     5 and 1    
Second Gear     Reverse     4 and 1    
Third Gear     Reverse     3 and 1    The clutch solenoid valves have a connector with two contacts. Connector contact "1" receives power from the power train ECM. See table 2 for the connections on the power train ECM. The connector contact "2" of the solenoid valves are joined together. These contacts return to connector J2-3 of the power train ECM.
Table 2
Solenoid Valves (Transmission Clutch)    
Direction or Speed    Solenoid    ECM Connector    
Forward Direction     2     J1-11    
Reverse Direction     1     J1-17    
First Gear     5     J2-8    
Second Gear     4     J2-1    
Third Gear     3     J2-7    Note: The solenoid coils are not designed for operation with a direct 24 volt DC signal. Activating the coils with a 24 volt DC signal will cause the life of the coils to be reduced. Use a 12 volt DC signal in order to activate the solenoid coils from a source that is not from the power train ECM.Note: Engagement of the neutral clutch is delayed for two seconds. This delay occurs between the selection of neutral by the operator and the engagement of the neutral clutch. The clutch solenoid valves for the transmission are not energized during this delay. This condition is called no clutch neutral. See System Operation, "Transmission Shifting Function" for more information on the no clutch neutral function.Torque Converter
The lockup clutch solenoid valve and the impeller clutch solenoid valves are part of the valve body that is located on the torque converter.Impeller Clutch Solenoid Valve
Illustration 2 g00855878
Impeller Clutch Solenoid ValveThe impeller clutch solenoid valve is an output of the power train ECM. The impeller clutch solenoid valve functions as a reducing valve. The impeller clutch solenoid