Their five wins from 19 games away was the fewest of the top five - they also drew 10 and lost four.
Ferdinand, 32, speaking after United's 3-1 win over Chicago Fire, said: "We had an unbelievable home record but our away form was shocking.
"It can get into your system. We were 2-0 up in games and got pegged back or lost. Hopefully we can put that record to bed."