4l60e TCC Apply Valve Kit Part No. 77805E-K Fits PWM units only! Vehicles with GM 4L60-E, 4L65-E and 4L70-E transmissions have numerous converter overheat lockup complaints. These include no lockup or lockup immediately after 2nd Gear when fluid warms up, caused by valve bore wear. Frequently, the solenoid will have no control over the valve’s position. Often converter feed oil will leak past the OE spool, which, added together with orificed signal oil will be more than the solenoid can exhaust. This may completely stroke the valve into the lockup position and create a “no power” or “no brake cancel” condition. Oil cross-leaks may float the valve into a mid-way position and restrict cooler flow, which burns up the converter. Sonnax TCC apply valve kit 77805E-K will eliminate the bore cross-leakage. This precision valve has a PTFE seal to prevent the cross-leaking of converter signal and converter feed oil. Updated stroke pressure eliminates TCC drift on apply and updated exhaust control PTFE seal eliminates cross-leaking of converter signal oil and converter feed oil Works in both early- and late-style PWM pumps when used with included spring Drop-in Zip Valve™ parts install quickly and easily