The Dutchman was officially unveiled as the Manchester United boss at a packed out press conference on Thursday afternoon less than a week after ending his World Cup campaign with the Netherlands.
Holland eventually finished third after beating Brazil last Saturday, and on his first appearance as the United manager, van Gaal claimed that he will be planning a meal with Ferguson to get his views on the club he ruled for 27 years before his retirement.
Speaking to the assembled media, Van Gaal said: "He called me to congratulate me [on the appointment] and we have spoken about a cup of coffee or to eat with each other.
"We were always invited to the elite [meetings] at Uefa, and we always got together with a glass of wine. We know each other very well, so I will drink coffee and drink wine with him. Maybe it will be some of the better wine, I imagine."
Despite being renowned as a supremely confident coach, Van Gaal is acutely aware of the size of the task that faces him after United finished a distant seventh last term - their worst-ever position in Premier League history.
David Moyes replaced Ferguson last season, but the Scot struggled and was eventually sacked in April after a harrowing campaign, and the former Everton boss was replaced in the interim period by Ryan Giggs, who has since been employed as assistant to Van Gaal.
"Every season you have to prove [yourself]. Last season you are seventh, so then you are not the biggest club," Van Gaal added. "When I was in China and Brazil, people were talking about United when I was coach of the Dutch team. There is a lot of expectation.
"The owners and the CEO have a lot of confidence in me, and my philosophy and because of that I am here, and we have to wait and see if I can fulfill this expectation of these people, but also of the supporters because they are very important."
The former Barcelona coach gets his United career underway next month with the first game of the new season against Swansea City at home.