PISTON & ROD GP 9Y8543 - Caterpillar

To ensure that the transmission oil does not overheat do not keep the torque converter in the stall condition for more than 30 seconds. After the torque converter stall test allow the transmission oil to cool before stopping the engine.
This test will determine if the oil pressure to the transmission lubrication circuit is sufficient.
Table 1
Required Tools    
Tool     Part Number     Description     Qty    
A     198-4240     Digital Pressure Indicator     1    
B     6V-3965     Fitting Assembly     1    Procedure
Illustration 1 g01086493
Right Side of Transmission (10) Test port for transmission lubrication oil
At test port (10), install tool (B) .
Connect tooling (A) onto tool (B) .
Run the engine at HIGH IDLE RPM in NEUTRAL. The pressure on the gauge must be approximately 110 kPa (16 psi).
When the test is complete, stop the engine and remove the test equipment.Result
If the oil pressure is too low, perform the Systems Operation, Testing and Adjusting, "Torque Converter Outlet Relief Valve Pressure - Test and Adjust". If the pressure of the transmission lubrication oil is still too low after testing and adjusting the torque converter outlet relief valve, perform the Systems Operation, Testing and Adjusting, "Torque Converter Inlet Oil Pressure - Test". If the oil pressure is still too low, the torque converter may need to be serviced.