Principles of Operation: Notes

WARNING: This page is about a different car, the 2011 Mercury Milan and 2011 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.

The Power Transfer Unit (PTU) is a gearbox that attaches to the transaxle. Vehicles equipped with the 3.0L engine have the 6F35 transaxle and those with the 3.5L engine have the Aisin AW21 transaxle. The PTU design is similar between the two. The RH intermediate shaft passes through the PTU and engages the differential side gear as in normal Front Wheel Drive (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.

Serviceable components of the PTU are limited to the output shaft seal and flange, intermediate shaft seal and deflector, cover seal and the PTU-transaxle compression seal. The internal components are not serviced. 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.