TransGo highlights its new oversize S4 regulator valve for 2018-on GM 8L45 and 8L90 transmissions.
According to TransGo, when General Motors made a change to the S4 regulator valve in both the 8L45 and 8L90 transmissions, the updated two-land design and computer command strategy resulted in significant increased wear, even at low mileage.
TransGo says it redesigned this two-land style S4 valve with an oversize hardened steel valve, lengthening the land on the clutch side to ride in an unworn portion of the bore, restoring hydraulic integrity of the circuit and sealing the signal oil side with a PTFE ring to ensure longevity. The product number is 8L90-S4LATE-OS.
According to TransGo, it can corrector reduce:
- Slip 1-2 or 1-3 shift;
- Harsh 1-2 or 1-3 shift;
- Clunk on coast downshift.