Differential

Bulletin number

9100931

Component

Power train

Summary

DIFFERENTIAL Rear Axle Some AWD Chrysler Pacificas are exhibiting a grinding noise coming from the PTU when it's shifting from 2WD to AWD. C1477-48 may also be present. To engage AWD, the DTCM energizes the hydraulic pump inside the RDM to apply the torque transfer clutch. This allows the propeller shaft to spin up to speed and match the front axle speed allowing the shift fork in the PTU to engage without clashing. The DTCM utilizes the pressure sensor on the RDM to determine the amount of hydraulic pressure applied to the clutches. If that pressure sensor fails, there can be inadequate pressure, preventing the driveshaft from coming up to speed when going into AWD. This will cause a grinding noise in the PTU. If the vehicle comes in with a grinding noise coming from the PTU, prior to replacing the PTU or RDM, replace the RDM pressure sensor 68227790AD and verify whether the concern has been resolved.

Owners of these vehicles have filed 6 complaints in the transmission category.