In real life, the Boeing 767-300 has a MTOW of 158,760 kg, and the Boeing 767-300ER has a MTOW of 186,880 kg. In-game, the Boeing 767-300 has a MTOW of 186,880 kg, which is incorrect as it is the Boeing 767-300 not the ER.
The MLW is also messed up. The Boeing 767-300 has 136,078 kg while the Boeing 767-300ER has 145,150 kg. In-game the MLW of the Boeing 767-300 is the same as the Boeing 767-300ER in the real world.