Ferguson does not believe City manager Mark Hughes, a former United player, will be able to buy success following the takeover at Eastlands by new owner Sheikh Mansour bin Zayed Al Nahyan.
Just three days after crushing Portsmouth 6-0 in the Barclays Premier League, City were dumped out of the Carling Cup in a penalty shoot-out by Coca-Cola League One Brighton.
And Ferguson believes the influx of cash into City, which has seen the arrival of Brazilian superstar Robinho, will not draw young fans away from United.
Ferguson told Inside United, the club's official magazine: "I think that supporting football clubs is an inherent thing, you normally follow the team that your father or your grandfather followed, that's the normal pattern.
"That loyalty remains all your life and it applies to fans of clubs up and down the country, big or small.
"What you're brought up with, it stays with you, and that's what supporting a team means. I don't think any 13-year-olds will be jumping ship because City have got a load of money!"
Ferguson also believes Hughes, who played for the Scot at United, will not be able to buy success.
He added: "I made the point at the time, it's all very well having all the money but you can't buy everyone. It was proved in the summer.
"We didn't want to sell Ronaldo, other clubs don't want to sell their best players, and there are only so many players you can buy."
Ferguson continued: "Back in the 1950s Sunderland were called 'The Bank of England Team' - and they got relegated. There are no guarantees.
"You can buy 11 individuals - you can buy 11 Robinhos but it wouldn't be a team would it?
"The art of management is building a team with balance, with certain characteristics that blend with each other - that's the most important thing.
"Mark Hughes will be faced with that situation having all this money and wondering what to do with it, and that can put you under a bit of additional pressure."
Despite the influx of cash at clubs like City the prospect of starting out in management at this time would not appeal to Ferguson.
He said: "I think it's a hell of a game now. The first thing is to make sure you keep your principles, no matter what. No job is worth it if your pride and your principles are stretched to the limit.
"Once the job starts to impinge on those two things, you need to decide whether you're in the right game.
"The problem is, football is steeped in most managers' blood. They've been in the game since they were kids, they all want to stay in the game and their dreams are still there, so that's what makes it difficult.
"When I started out I didn't have any money, so sticking with your principles is difficult when you've got three kids to feed, but it's still so important."
Ferguson points to Kevin Keegan and Alan Curbishley who left Newcastle and West Ham respectively because they disagreed with what was going on at the clubs.
He said: "Look at what happened with Alan Curbishley - he did the right thing by walking away, and Kevin Keegan, which was a similar situation.
"There's only so much you can take. At the end of the day you're not the manager any more - I don't know why they employ them in some situations."
Ferguson also claimed he knew Cristiano Ronaldo would not suffer a backlash from fans despite looking like he might move to Real Madrid in the summer.
"The fans know he's been here for five years, he's shown his loyalty to the club - he's hardly missed a game in all that time - and he's scored all these goals," said Ferguson.
"He's entertained us to incredible levels and the fans don't forget these kind of things. They supported him after the World Cup thing with Wayne Rooney and I knew they would support him again this time."
by espnstar.com