Invention Grant
- Patent Title: Method for synchronized four wheel drive low range shifts with vehicle in motion
-
Application No.: US18362285Application Date: 2023-07-31
-
Publication No.: US12000478B1Publication Date: 2024-06-04
- Inventor: Frank C Thompson, IV
- Applicant: FCA US LLC
- Applicant Address: US MI Auburn Hills
- Assignee: FCA US LLC
- Current Assignee: FCA US LLC
- Current Assignee Address: US MI Auburn Hills
- Main IPC: F16H61/32
- IPC: F16H61/32 ; F16H61/664

Abstract:
A method of controlling a four wheel drive (4WD) low range shift in a vehicle is provided. The vehicle has a powertrain including a transmission that drives a transmission output shaft to provide drive torque to a driveline including a power transfer unit (PTU) that delivers torque to front drive wheels and a rear differential unit (RDU) that delivers torque to rear drive wheels. The PTU and RDU are selectively rotatably coupled to each other through a propeller (prop) shaft. The PTU and the RDU are commanded into a neutral position. A clutch at the RDU is commanded to selectively engage to a degree that communicates a desired amount of torque from the prop shaft to the RDU. A determination is made that an output speed of the transmission output shaft is synchronized to match a speed of the RDU and the RDU is commanded to shift into 4WD low.
Information query