Installation of power and data cables between the P1 and P3/P4 structures in preparation for solar array deployment

Performing final tasks required for activation of the Solar Alpha Rotary Joint (SARJ); the SARJ is an automobile-sized joint that will allow the station's solar arrays to turn and point toward the sun; they also prepared the P3/P4 truss and its solar arrays for operation by setting the stage for deployment of the truss' radiator

Replacing a depleted nitrogen tank and a device used to help the flow of coolant from the truss, the backbone of the station. They also removed thermal covers from the Japanese Kibo module to inspect the berthing mechanism where the module's exposed facility will be installed during the STS-127 mission in 2009. They also started inspecting, cleaning and lubricating the starboard SARJ and begin replacing 11 of 12 trundle bearings. One was replaced during the STS-124 mission in June 2008.

Relocating two equipment carts, setting the stage for the installation of the starboard S6 truss (scheduled for February 2009). The spacewalkers also lubricated the end effector, or hand, of the Canadarm2, the station's robotic arm. They also continued lubricating the starboard SARJ and replacing trundle bearings.

Completing starboard SARJ cleaning, lubricating and trundle bearing work.