Transfer Case - Power Transfer Unit (PTU)

System Operation 

The PTU is a gearbox attached to the transaxle. The RH intermediate shaft passes through the PTU and engages the differential side gear, similar to FWD applications. The PTU directs power to the rear driveshaft through a helical gear spline coupled to the transaxle differential case, a helical gear drop (idler gear) and hypoid/helical ring gear assembly and pinion set. The PTU is sealed from the transaxle and has its own oil sump.

The internal components are not serviceable. Do not remove the cover of the PTU. If any of the geared components, bearings, case cover or internal shafts are worn or damaged, a new PTU must be installed.

The following components of the PTU are serviceable:

• Compression seal
• Cover seal
• Intermediate shaft seal and deflector
• Output shaft seal and flange
• Input shaft seals

Heat Protection Mode 

During very extreme off-road operation, the AWD system utilizes a heat protection mode to protect the ATC solenoid (part of rear axle) from damage. If the system detects an overheat condition, it enters a locked mode. If the heat in the system continues to rise once in the locked mode, the 4X4 control module disables the ATC solenoid. Before continuing with normal operation, allow the system to cool down at least 10 minutes with the ignition switch in the ON position.