2006 and newer General Motors vehicles equipped with 6L45, 6L50, 6L80 and 6L90 automatic transmissions often come in with complaints of lock-up cycling or a surging sensation, as well as shift solenoid or TFP performance codes due to sticking clutch select valves.
The lock up cycling complaint is often due to the poor resolution (accuracy) of the original equipment TCC regulator valve and spring in relation to the TCC solenoid function. The torque converter clutch regulator valve function is to regulate the torque converter clutch apply pressure. The computer varies the pulse width modulation of the TCC solenoid to control the slip speed of the lock-up clutch. The OE design valve and spring calibration does not provide adequate resolution under all driving conditions which leads to the TCC slip cycling. The new design TCC regulator valve and spring provides a higher degree of accuracy in controlling the slip speed, especially at lower road speeds. The difference in drivability is quite remarkable.
The clutch select valves direct fluid to various clutch elements depending on the shift solenoid command status. The OE select valves are prone to sticking or dragging in their bore. When one of the clutch select valves sticks or drags, the computer sets a solenoid performance or TFP switch code. The computer assumes that the solenoid did not function correctly as the computer has no way to determine if the solenoid, clutch select valve or the TFP switch malfunctioned. The solenoid performance and TFP codes are very misleading. Quite often, the real problem is the clutch select valve sticking in the bore. Sticking or dragging clutch select valves often lead to unnecessary solenoid replacement.
Features & Benefits:
The TransGo drop-in redesign USA-made hardened steel TCC regulator valve, features longer lands which restores the hydraulic integrity of the circuit by utilizing previously unused and therefore unworn areas of their bore. In addition, the special design valve and spring calibration enables the computer to control the TCC regulation more accurately, which results in better slip control. Lastly, the drop-in USA-made hardened steel clutch select valves greatly help prevent the valves from sticking in their bores.
Corrects/Prevents/Reduces:
Shift solenoid performance codes or false P0751 due to sticking or dragging clutch select valves
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