In Toyota/Lexus U151E, U151F and U250E, the B3 orifice control valve and spring are biased by SLT solenoid (torque signal) pressure to control the UD/B3 brake. Regulated line pressure is routed from the 4-5 shift valve through the B3 orifice control valve to apply the UD/B3 brake. When this valve sticks, flow will diminish or no flow will go to the brake, resulting in burnt clutches or shift complaints. Reconditioning the bore and installing Sonnax oversized B3 orifice control valve kit, 27741-16K prevents future sticking.

• Hardcoat anodized aluminum valve combats premature wear
• Valve front spool has been greatly lengthened to provide more stability in the bore
• Annular grooves provide better valve centering in the bore and keep the contact area lubricated to prevent seizure