Possible reasons for delayed gear shifting in a Nissan automatic transmission:
Mechanical problems:
*Low or contaminated transmission fluid
* Worn or damaged friction discs
* Faulty torque converter
* Worn or damaged shift solenoids and sensors
Electrical problems:
* Faulty speed, throttle position or engine speed sensors
* Damaged wiring or connectors
*Transmission control module (TCM) problems
Software problems:
* Outdated or corrupt TCM software
* Malfunctions in the automatic transmission control system
Other possible reasons:
* Increased load on the transmission due to improper operation or towing heavy loads
* Worn or damaged drive shaft
*Differential problems
Recommendations:
1. Check the transmission fluid level.
2. Replace transmission fluid and filter.
3. Conduct automatic transmission diagnostics using a scanner.
4. Have any defective components repaired or replaced by a qualified mechanic.
5. Follow the maintenance schedule and use the recommended original transmission fluid.
6. Avoid sudden acceleration and towing heavy loads.