Narrative:

Received EICAS message 'gear disagree' followed by 'gear doors' message for the left gear during gear retraction. We ran the 'gear disagree' checklist; which had us dropping the gear. We had a normal gear down indication. Flight attendant called us and said the flight attendant at 3L heard a very loud grinding sound during gear retraction. We discussed the situation and decided we may have damage to the gear and or the tires. I was talking to dispatch over ACARS; then dispatch tried to call us on radio; we had intermittent communication; but were not able to have clear communication because we were so low (5;000 feet). I told them to use sat com; but we were unable to get sat com established. I called them on my cell phone; and got through to dispatch and [maintenance]. We discussed fuel dumping and a return to ZZZ. I [advised ATC]. We decided; instead of flying box patterns with a lot of vectors; to hold over the ZZZ VOR at 5;000 feet. We informed approach of our intention to dump fuel. We dumped 48;000 pounds to get below max landing weight and to get us as light as possible for landing in case we had damage to the left gear and or tires. After fuel dumping; we made an uneventful landing back at ZZZ; at 348;000 pounds. Once on the runway; I wanted the fire department to check the left main landing gear area for damage. I had the APU on; and we shut down the left engine. The fire department informed us of no damage. I then taxied to the gate and shut down. Once at the gate; a mechanic came to the cockpit and told us we sheared off a gear actuator rod at one end.

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Original NASA ASRS Text

Title: B767 flight crew reported a GEAR DISAGREE and GEAR DOORS EICAS message after takeoff; dumped fuel and returned to departure airport. Post flight inspection revealed a sheared left main gear actuator rod.

Narrative: Received EICAS message 'Gear Disagree' followed by 'Gear Doors' message for the left gear during gear retraction. We ran the 'Gear Disagree' checklist; which had us dropping the gear. We had a normal gear down indication. Flight attendant called us and said the flight attendant at 3L heard a very loud grinding sound during gear retraction. We discussed the situation and decided we may have damage to the gear and or the tires. I was talking to dispatch over ACARS; then dispatch tried to call us on Radio; we had intermittent communication; but were not able to have clear communication because we were so low (5;000 feet). I told them to use Sat Com; but we were unable to get Sat Com established. I called them on my cell phone; and got through to dispatch and [maintenance]. We discussed fuel dumping and a return to ZZZ. I [advised ATC]. We decided; instead of flying box patterns with a lot of vectors; to hold over the ZZZ VOR at 5;000 feet. We informed approach of our intention to dump fuel. We dumped 48;000 LBS to get below max landing weight and to get us as light as possible for landing in case we had damage to the left gear and or tires. After fuel dumping; we made an uneventful landing back at ZZZ; at 348;000 LBS. Once on the runway; I wanted the fire department to check the left main landing gear area for damage. I had the APU on; and we shut down the left engine. The Fire Department informed us of no damage. I then taxied to the gate and shut down. Once at the gate; a mechanic came to the cockpit and told us we sheared off a gear actuator rod at one end.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.