Search results
Results from the WOW.Com Content Network
A transmission solenoid or cylinoid is an electro-hydraulic valve that controls fluid flow into and throughout an automatic transmission. Solenoids can be normally open or normally closed. They operate via a voltage or current supplied by the transmission computer or controller. Transmission solenoids are usually installed in a transmission ...
The police package (9C1) B-body cars featured a First Gear Block Out (FGBO) Plate on the transmission housing to prevent drivetrain damage. The shift point for first to second gear is about 43 MPH (69 km/h) while second to third gear shift point is about 83 MPH (134 km/h) assuming a 3.08:1 differential and a 5,500 RPM engine speed limit.
A transmission control unit (TCU), also known as a transmission control module (TCM), or a gearbox control unit (GCU), is a type of automotive ECU that is used to control electronic automatic transmissions. Similar systems are used in conjunction with various semi-automatic transmissions, purely for clutch automation and actuation.
The 4L80-E uses two shift solenoids, initially called Shift Solenoid A and Shift Solenoid B; they were later changed to comply with OBD-II regulations to 1-2 shift solenoid and 2-3 shift solenoid. By activating and deactivating the solenoids in a predetermined pattern by the PCM, four distinct gear ratios can be achieved.
A variable force solenoid (VFS) is an electro-hydraulic device that controls pressure proportionally or inversely proportionally to a signal (voltage or current) obtained from the on-board controller of a powertrain. A low flow VFS is used as a signal level devices for transmission line pressure control or application of clutches.
Some areas of failure on this transmission include leaks in the oil filling tube by removing the cap incorrectly, damage to plastic internals due to fluid over-temperature conditions, leaks in the transmission oil cooler, internal fluid pressure leaks from torn piston diaphragms, worn piston bores for solenoids in aluminum valve body, and the resulting worn clutches and bands.
Pushing a button on the shift control preselected the chosen gear. The electrical circuit was closed only after the driver fully depressed the clutch pedal. This energized the appropriate transmission mounted solenoids necessary for returning the transmission to neutral and then completing engagement of the preselected gear.
The RL4R01A is a hydraulic controlled unit for its main operation. Shift timing is based on throttle cable position and governor pressure. Its only electronic parts are two solenoids, one for the torque converter clutch, and the other for the manual overdrive cancel switch, but these do not affect the gears control and passing.