Reasons for automatic transmission slipping:
Low or contaminated transmission fluid:
* Insufficient fluid can cause loss of pressure and lubrication, resulting in slipping.
* Contaminated fluid contains wear and contaminants that can clog hydraulic passages, preventing smooth shifting.
Solenoid failure:
* Solenoids are responsible for shifting gears and regulating fluid flow.
*A faulty or dirty solenoid can cause delays or slipping when shifting.
Torque converter malfunction:
* The torque converter transmits torque from the engine to the gearbox.
* Worn or damaged torque converter can cause loss of traction and slipping.
Worn friction discs:
*Friction discs inside the transmission create the clutch needed to change gears.
* Wear on discs over time reduces their effectiveness, which leads to slipping.
Speed sensor malfunction:
* The speed sensor tells the transmission the current vehicle speed.
* Incorrect speed sensor readings may result in incorrect gear selection and slipping.
Transmission control module (TCM) malfunction:
* The TCM controls transmission operation, including gear shifting and fluid pressure adjustment.
*A faulty TCM may send incorrect signals causing slipping.
Other possible reasons:
* Low vacuum level (on vacuum controlled models)
* Faulty throttle valve
* Flywheel wear
*Wiring or grounding problems