Behind the Wheel with Phil Lebeau

Barra broke glass ceiling, but real challenge is ahead

General Motors CEO Mary Barra
Andrew Harrer | Bloomberg | Getty Images

Mary Barra, the incoming CEO of General Motors, is trying to pull off one of the trickier moves in the business world.

No, it's not becoming the first woman to lead a major automaker—that achievement should be heralded for all it represents, but her gender will not determine if she's successful in her new role.

Instead, the measurement of her success relies on whether she can evolve the automaker to become even more competitive, profitable and perhaps live up to its potential.

(Read more: First female CEO shatters Detroit's glass ceiling)

But at a company that has struggled to recruit transformational CEOs—particularly when they are chosen internally—the automaker's latest selection raises one big question: Can a 33-year veteran of GM drive major change at the automaker?

"She has the experience internally and knows who the players are as CEO," said Jessica Caldwell, a senior analyst at Edmunds.com. "It definitely seems like a solid pick by GM."

'No more crappy cars'

Barra comes into the CEO job after a successful run as the company's global head of product development.

Under her watch, she famously told GM engineers that there are no excuses, bluntly saying there could be "no more crappy cars."

A look at the company's latest models suggests they have so far heeded her warning. The Cadillac ATS and CTS, the new Chevy Corvette Stingray and the new Chevy Malibu are all examples of General Motors building new vehicles that can attract buyers and command premiums. The CTS was even named the 2014 Motor Trend Car of the Year.

(Read more: Kyle Bass takes stake in 'undervalued' GM)

Unfortunately, GM also has a well-worn track record of building a few great models, and then rolling out forgettable cars and trucks. Barra's challenge lies in getting the product side of GM to stay on its game.

Mary Barra to succeed Akerson as GM CEO
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Mary Barra to succeed Akerson as GM CEO

She'll have help from Mark Reuss, who took her job as the head of global product development. The two have the chops and vision to force GM designers to stay focused, but now they have to show it.

Will every model they roll out be a hit? No.

Will there be a clunker or two in there? Probably.

They won't bat a thousand, but if they have more hits than strikeouts, it would go a long way in keeping GM competitive.

Push middle management and old guard

The other challenge Barra faces is pushing GM's middle management and old guard to think and act differently—something that's easier said than done.

She saw the absurdity of some long-entrenched GM rules and habits when she was in charge of human resources, which included an out-of-touch, 10-page dress code. Talk with enough executives in middle management at GM and you'll hear similar stories from other departments: many have been there for years, and they realize some of the practices are cumbersome and should be revamped.

(Read more: Government sells the last of its GM stake: Treasury)

Can a woman who grew up in that culture force it to change? Her track record says yes. But another problem plaguing GM is that the farther up its executives climb, they become less effective in getting those in middle management to move faster.

One example is Fritz Henderson, an internal selection who said that he would change the culture at GM when he took over for Rick Wagoner in 2009. He was only around for eight months and failed to make major changes in how GM operated.

If Barra can buck that trend, she has a shot at being a transformational CEO—and not simply because she's the first woman to run General Motors.

—By CNBC's Phil LeBeau. Follow him on Twitter @LeBeauCarNews.

Questions? Comments? BehindTheWheel@cnbc.com.