Regarding your question, the main reason should be the failure of the pressure valve. You should first check whether the quality of transmission oil is normal. It may be that the pressure of each pressure valve cannot reach the normal value accurately after the transmission oil deteriorates. If the vehicle is used for a long time, sometimes even the newly changed oil will be dirty again in a short time. The gearbox oil can only be changed a part at a time, and it will be dirty after running for a few kilometers, which will lead to this phenomenon; At the same time, it will also lead to the blockage of the solenoid valve. It is recommended that you check and change the transmission oil first, and change it several times every few kilometers, and then change the solenoid valve to avoid the solenoid valve from being damaged again. It is also possible that the oil pump is worn or blocked, or the friction plate is ablated. I hope my answer is helpful to you.
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