"We don't talk to Phil on first-name terms any more - its "coach"," he added.
"He's changed his number, he won't let anyone call him. I used to speak to him and text him and stuff but he won't have it any more - he's a changed man so far really."
Ferdinand has also revealed that new United boss David Moyes has not changed much in terms of the players' individual training routines, which are particularly applicable to the 34-year-old and Ryan Giggs.
"The manager knows Ive got a certain way that I need to train, that I know my body - like Giggsy as well," he continued. "He has kind of left it open to us to continue what we were doing to get us [playing] like last season.
"Thats been fantastic for me because you get worried a little bit and think, 'Oh, it's a new manager, is he going to let us continue our regimes that we're involved in to get us out to play football and to train every day?'"
"But it's the sign of a great manager that he has."
The former England defender has also given an insight into how Moyes has adapted to replacing Sir Alex Ferguson.
"The new manager is quick to join in the banter but when it's work time, it's work time," he added.
"The players at Manchester United aren't there to mess about on the training pitch, we're there to enjoy ourselves but to be drilled and to make sure we're all going in the same direction, and that's to be successful."