Vehicles with GM 4T60, 4T60-E and 4T65-E transmissions may exhibit multiple line pressure and converter-related problems due to excess wear in the main pressure regulator bore. Wear at the balance spool end allows critical fluid loss, resulting in high line pressure, harsh shifts, and overheating due to reduced cooler/converter flow. Wear at the outboard spool robs converter feed pressure and lowers line pressure, resulting in soft shifts and burnt clutches. Reconditioning the bore and installing Sonnax oversized pressure regulator valve kit 84754-46K restores hydraulic integrity for proper line pressure control and improved shifting in all ranges.

• Case-hardened steel valve combats premature wear
• Annular groove helps center valve in bore to reduce future side-load wear