The 71-year-old Scot, who shelved retirement plans more than a decade ago, still has no idea when he will call it a day.
"There's no getting rid of me," Ferguson, who has been in the Old Trafford hot seat since 1986, said in an interview with twentyfour7 Football magazine.
"I will probably become a director.
"Nobody knows (when I will step down), neither do I. It won't be a doctor that tells me to quit."
Ferguson, whose side have a 12-point lead at the top of the Premier League, has guided United to many titles including two Champions League trophies, five FA Cups and 12 league crowns.
Even though he is still in the job, there is often media speculation about who will fill the vacancy once it comes up.
Real Madrid's Jose Mourinho, a good friend of Ferguson's who is heading to Old Trafford this week for Tuesday's Champions League last 16 second leg, is one of the most heavily fancied candidates.
Ferguson said he expected to be consulted about a successor but that the final decision would not be his.
"They'll ask me," he said. "But I think it'll be a club decision not mine."
Whoever comes in might want to listen to his words of advice.
"Imagination is always important. The other most important thing is don't change who you are," he said.
"It happens, you see it time and time again, a manager comes in and tries to change himself.
"Your job is not to change you, it's to change what you're taking over. Change the team, the philosophy of a football club to your philosophy. Never change who you are.
"That really will hold you in good stead, simply because the players understand what you are, who you are."
Ferguson added he was keen to ensure that former United players stayed involved in the club.
"Looking at my present crop, it's difficult, but the likes of (Ryan) Giggs and (Paul) Scholes will be part of the structure here. Darren Fletcher in the long term possibly and Nicky Butt is with the reserves," he said.
"We try to get as many former players in the set-up as we can, we've got a good back-up.
"We look ahead because that is succession planning in terms of structure - they've the experience of being at the club, being a player here, knowing what it takes to be a winner. It's good to have it here, keep it within the club."