The 2020 Ram ProMaster City's 9-speed automatic transmission can develop shuddering during acceleration. Understanding this transmission helps address this common complaint.
948TE 9-Speed Transmission
The 948TE is a ZF-designed 9-speed automatic used across multiple FCA vehicles. It provides good efficiency but has been subject to various complaints regarding shift quality.
Causes of Transmission Shudder
Torque Converter Clutch Issues
The TCC can develop shudder from worn friction material or contaminated fluid. This is most noticeable at steady cruising speeds.
Shift Adaptation Problems
The transmission learns clutch engagement points. Corrupted or improper adaptation causes rough shifting and shudder.
Fluid Degradation
The 9-speed requires specific fluid. Degradation or wrong fluid type causes shift quality issues.
Software Calibration
FCA has released numerous software updates addressing 9-speed shift quality. Outdated calibrations may produce shudder.
Commercial Use Impact
Stop-start commercial use stresses the 9-speed's complex clutch pack arrangements, potentially accelerating wear.