The B3 orifice control valve often sticks in the casting bore, preventing proper stroking of the valve and flow control to the UD/B3 brake.
Refurbish the valve bore and install the Sonnax oversized B3 orifice control valve and spring to prevent future sticking issues.
In U151E/F, U250E units, 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.
Sonnax valve body layouts provide a detailed overview of individual units making it quick and easy to determine what’s available for the specific valve body you’re working on. See all Sonnax valve body layouts.
January 21, 2013
Topics: Vacuum Testing Vacuum Test Guides Transmission Toyota/Lexus U250E Transmission U151F Transmission U151E TransmissionRead Now
September 30, 2005
Topics: Diagnostics And Theory TransmissionRead Now
Contact a Sonnax Parts Distributor.
The OE valve is stuck in the bore.