December 09, 2013
Wear at the accumulator bores or on the critical diameters of the accumulator pistons in the listed Toyota/Lexus units is very common. The B1, B2, B3 and C2 accumulator pistons are all the same size and are used during apply of the clutches and brakes to ease the engagement of the apply component. Wear at the valve body bore allows clutch/brake apply oil to exhaust, resulting in harsh or delayed apply of the clutch or brake, burned clutches and brakes, or slipping and flares in the associated gears.
Sonnax B1, B2, B3, C2 accumulator piston kit 47740-11K incorporates an O-ring for positive sealing, even in worn bores. This one kit will work in any of the four bores.
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.
A vacuum test at the port indicated fails to hold at least 18 in-Hg, or if visual wear in bore or on the accumulator piston is detected.