Typical complaints about vehicles with Ford A4LD transmissions include soft shifts, low line pressure and/or converter apply problems. A worn valve body bore at the pressure regulator valve can often cause these complaints. Line pressure is allowed to leak to exhaust, preventing the valve from stroking properly and feeding the converter apply circuit. Sonnax oversized pressure regulator and boost valve kit 56947-06K restores the hydraulic integrity of the circuits.

• Hardcoat anodized aluminum valve combats premature wear
• The converter apply spool land has been lengthened to increase spring force against the oversized valves
• Two stiffer springs have been included in the kit, to be used only for the late valve bodies (2nd and 3rd designs)
• A high ratio boost valve kit is included to counteract the increased balance diameter on the pressure regulator valve