United have let David de Gea occupy the sticks for all competitions this season, while Sergio Romero started in EFL Cup and Europa League games.
Jurgen Klopp meanwhile, has had a problem trying to establish his No.1 shot-stopper and he keeps rotating between Loris Karius and Simon Mignolet.
Whereas Arsenal switched between Petr Cech and David Ospina last term.
And Ferdinand thinks uncertainty in this area can be an Achilles heel for some teams.
The BT Sport pundit insists United regularly collected titles, because they knew which keeper they would be playing.
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“You have got to build relationships with the players on the pitch,” Ferdinand told BT Sport.
“Two centre-halves and the goalkeeper, that’s a triangle.
“I had that with Edwin Van Der Sar and [Nemanja] Vidic and it became telepathic.
“You can’t get that chopping and changing. You need to play games consistently.
“It’s like when you play for England, you play two, three, four games, you don’t feel a part of it.
“You need ten, fifteen games to feel a part of it.
“And that’s the way the keepers will be as well.”
When Ferdinand was told by Gary Lineker that Arsenal change keepers for cup competitions, Ferdinand said: “They don’t win the league, though, that’s why.”
United will be hoping to maintain their good start to the season when they host Everton on Sunday (1:30pm).