SEAL-O-RING 9N1552 - Caterpillar

Lockup Clutch Function
The lockup clutch controls the direct drive electrically. When the ECU activates the lockup solenoid the lockup clutch in the torque converter mechanically connects the torque converter input shaft to the torque converter output shaft. This mechanically connects the transmission to the engine.The ECU keeps the lockup clutch engaged as much as possible during normal operation. When the transmission shifts the lockup solenoid is deactivated for easier shifting. The vehicle is in torque converter drive when the lockup solenoid is deactivated.The transmission's reverse gear and the transmission's neutral gear are torque converter drive. Direct drive means that the transmission output shaft is mechanically connected to the input shaft.Maximum Forward Gear Function
This function limits the operation to the available range of gears of the vehicle. The ECU prevents upshifting to any gear that is greater than top gear. The value for top gear is stored in the ECU. The value of the top gear is programmable by the service personnel. The value of the top gear is programmed at the factory to the maximum top gear for the particular vehicle model.Note: The Caterpillar Electronic Technician (Cat ET) service tool can be used to program the top gear function. Use the configuration screen in the Cat ET service tool in order to change the top gear setting.The range of numbers for the CX31 are listed below. Factory setting ... 6Range ... 1 to 6Alternate Maximum Gear Function
The alternate maximum gear feature allows you to set a second maximum gear limit for each shifter. The feature is activated by moving the alternate maximum gear switch to the on position.When the feature is activated in the roading and the auto shift pumping configurations, the transmission will not force downshifts to the new top gear if the curren transmission gear is above the new top gear, but the transmission will inhibit the upshifts and allow the downshifts until the new top gear has been attained.When the feature is activated in the draw works configuration, the transmission will shift directly to the new top gear if the current transmission gear is above the new top gear and the engine speed is less than 850 rpm.Rapid Downshift Function
The ECU does not allow a turnaround shift until a short time after a shift occurs. A turnaround shift is an opposite shift from the previous shift. For example, a downshift is prevented for a short time after an upshift and an upshift is prevented for a short time after a downshift. The turnaround feature allows the conditions to stabilize before an opposite shift. The delay prevents hunting between gears.Elevated Shift Function
This function improves retarding performance by elevating the upshift and the downshift points. When the retarder on the service brake is engaged, the ECU raises the shift points.When the engine retarder is on, the upshift and downshift points are raised because the retarder systems are more effective at higher engine speeds.Shifter Selection Function
The ability to have two shift selectors is desired for some applications. This