丰田和雷克萨斯U660E/F and U760E/F six speed automatic transmissions can experience several problems which can be traced back to the secondary pressure regulator valve. These include transmission overheat, bushing and bearing failures along with other lube related failures. TCC operation can also be negatively affected.

One cause for these problems is bore wear at the secondary pressure regulator valve. This allows SLT and/or balance oil to leak, resulting in low cooler and lube circuit pressures. To restore the bore and correct circuit pressures, ream the bore and install the Sonnax oversized secondary pressure regulator valve kit, 47740-26K.

• Hardcoat anodized aluminum valve combats premature wear
• Annular grooves on the valve help center it in the bore to reduce future side-load wear