Transport of spare parts from a cargo carrier to a stowage platform on the station's truss. These parts include: an antenna, a pump module and a rail mechanism that allows a transporter to move up and down the truss. They also relocated a grapple bar onto an ammonia tank assembly as a get-ahead for the STS-129 mission, targeted for November 2009. A planned installation of a camera on the Japanese Experiment Facility was postponed to a future EVA for want of time.

Replacing the final four batteries on the port truss.

Removing covers from the Dextre robotic arm, reconfigure cables on a panel for some circuit breakers and deploy two additional payload attachment systems. They also installed a second camera that will provide video of experiments on the aft end of the exposed facility, a work, which was originally scheduled for EVA 4. Finally, they replaced an aging camera system on the starboard truss. Instead some get ahead tasks were completed which included installation of handrails and a portable foot restraint.

Inspection and replacement of a pump controller box on the station’s far port truss (P6) suspected of leaking ammonia coolant.