As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WE DEP DTW WITH 10.1 IN L AND 10.2 IN R TANK 1 HOUR INTO THE FLIGHT WE HAVE A 1000LBS DIFF BETWEEN TANKS 7.1 IN L AND 6.0 IN R. @ THE GATE AFTER BLOCK IN L 6.2 R 4.6 FUEL IMBALANCE AFTER 1:26 MIN IN A REMOVED AND REPLACED RIGHT DEFUEL VAVLE IAW UPS B757 AMM 28-26-01-401. OPS CHECK GOOD IAW UPS B757 AMM 28-26-01-790-801. REMOVED AND REPLACED L/W MAIN TANK FUEL SHUTOFF VALE IAW UPS B757 AMM 28-21-02-401. OPS CHECK GOOD. VALVE LEAK CHECK GOOD.