Toyota U340E

Transmission general data

The 4-speed automatic gearbox Toyota U340 (U341) has been used since 2000 on FWD Toyota Avensis, Corolla etc. with engine capacity up to 2 liters. One more leading transmission which is commonly met in repair services.This transmission was designed together with U140\ U240 (and identical in design) and was a very popular transmission in the field of repair among Aisin gear shifting units. The modification U341E provides higher torque, therefore it is used in engines with higher operational capacity Celica (1.8 l), the U341F unit is the version for four-wheeled vehicles (4WD).

Technical issues and repair guidelines

The whole mechanical and hydraulic part of these transmissions is very robust and the service life before the 1-st major repair is above 200-300 thousand kilometers depending on the driving style of auto users. During the first years U340-341 units require timely change of fluid and filter replacement. After some period of operation and due to frictions wear-out (torque converter in particular), the fluid gets contaminated more rapidly and that results in more frequent ATF change. Frequent change of automatic transmission fluid postpones the replacement of the torque converter lining. One of the most common problems is the oil leakage from the pump seal located between the gearbox and the torque converter. The seal is changed together with the bushing.

One of the most common parts to be replaced in new units (produced since 2009) is the EPC solenoid, which operates in much more intensive way than others. This transmission gets out of order after continuous operation in contaminated ATF with worn-out rings and seals. Timely change of ATF and repair of rings included in the repair kit makes it possible for this solenoid to operate during the whole period of the transmission usage period.

Typical issues with valve body and solenoids in U340

The electrical components of this transmission are quite durable, therefore the whole U340 unit may be considered as a very reliable transmission. However, during each disassembly procedure of this gearbox, specialists usually rebuild and clean the valve body and solenoids, which get damaged because of contaminated ATF. The clogged valve body may lead to unpredictable slippage in the package, where the fluid is not transmitted through corresponding valve body plunger. Long-term operation of this transmission with such problem leads to premature wear of practically “invincible” friction components in this unit.