A B767-300 International Captain reported receiving a 'BRAKE TEMP' warning after takeoff. The aircraft had been serviced with two new main gear tires prior to departure. It was determined after landing that one of the tires had been installed incorrectly.

Narrative

Relief pilot discovers a flat tire on right inboard front side of main landing gear during preflight walk around. We report to maintenance flat tire discrepancy via radio with gate and tire location and followed up with code via ACARS. Mechanic Supervisor came to cockpit and said 'Tire has pressure and is not flat'. I directed Relief Pilot to show Maintenance Supervisor the flat tire who then acknowledged it and then both front tires were changed on that gear. In the cockpit I asked the Lead Mechanic 'Are all the parts put on correctly and are we good to go?' He responded; 'All the parts put on correctly and you are good to go'. After takeoff we get a brake temp light. The gear was lowered to cool the brake temperature. After completion of irregular procedures checklists; Dispatch and Line Maintenance were contacted followed by a thorough discussion of aircraft issues and the safest course of action for our flight. It was determined by Dispatch and the pilots that it was safer to continue to destination enabling the aircraft to land at the lowest weight and slowest landing speeds versus an overweight and a much higher speed landing. The Purser was briefed on the condition of the aircraft. A Flight Attendant was debriefed on unusual noises she heard. An emergency was declared with approach and the fire trucks were requested as a precaution for possible flat tires and or dragging or locked brakes on right main gear. The passengers were informed just before landing that fire trucks had been called as a precaution. An uneventful soft landing with minimal braking and taxi occurred. The aircraft was parked at a hardstand site and passengers deplaned content as if a normal flight. Mechanics said that the right inboard front wheel of main gear was not installed correctly and was missing a retainer spacer for bearings. Numerous parts were picked up by the fire trucks from the runway after landing.