(at around 1h 9 mins) The position of the body of the charioteer killed in the training session at Sheik Ilderim's camp changes.
During the chariot race, in the wide shots of Messala, Ben-Hur is behind him, then the shots to Messala's right have his and Ben-Hur's horses neck-and-neck.
The young Judah is alternately wearing his yarmulke and bare headed while chasing Ester's dove around the square.
(at around 39 mins) The saw Christ is using remains in the same spot, despite Him creating enough friction with the blade to cut deeper into the wood.
At one point in the chariot race a man in modern clothing - light-colored shirt, long pants, dark shoes - can be seen running out of the crowd onto the track and waving his arms at the camera. That was assistant director William Wyler, who saw that one of the chariots - out of camera range - was approaching the curve of the track too fast and Wyler was signaling the director to have the crew cleaning up a crashed chariot to get out of the way.
A camera is visible during the chariot race.