Toyota/Lexus vehicles equipped with A750E and A750F transmissions may exhibit 5th Gear complaints and a burnt B1 brake as well as low line pressure, resulting in poor shift quality and slipping in Forward or Reverse. These issues can often be traced to wear in the B1 apply control plunger sleeve, which allows line pressure to escape and cause drivability concerns.
Installing Sonnax B1 apply control plunger kit 147741-55K eliminates pressure loss, revives B1 apply pressure control and restores shift quality.
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.
Vacuum testing at the port(s) indicated fails to hold the recommended minimum in-Hg, or if wear is visually detected.