There certainly are limits, industry insiders admit, and challenges to truly common, global and scalable platforms are considerable.

Chief among them are the variety of global safety and emissions standards.

“You have new fuel-economy legislation in China, new fuel-economy legislation in Brazil,” notes Chernoby. “And guess what? The tests they run, the metrics they’ve come up with are different from the U.S. and Europe. And the U.S. and Europe aren’t the same.

“It is somewhat possible to try to (design) a vehicle that meets all these requests, but if you try chasing that, your weight can get out of control, which has an effect on fuel economy and performance.”

Global safety regulations are a heavy consideration when imagining new vehicle platforms, agrees Nand Kochhar, global chief engineer-safety and product development for Ford.

“The strategy in general is to design the platform for good safety performance and then tailor the top hat for meeting those regional needs,” he says, alluding to different cost, fuel-economy, emissions and customer requirements from one market to the next. “In addition to meeting the standards, we want to be competitive.”

The supply chain also presents hurdles to going common, although the economies-of-scale potential certainly has automakers seeing dollar signs.

A recent AlixPartners study estimates doubling production volumes off a single platform can slash non-recurring costs 10%-20% and trim recurring outlays 4%-8%, equating to several hundred dollars in savings per vehicle.

“Every jump up (in volume) gives you more leverage in talking with suppliers,” Hoffecker notes.

But in some regions, suppliers already have stretched capacity thin. In many cases, tooling up for these multimillion-unit platforms could require new investment, and that easily could eat away the potential savings.

“It used to be in the early part of the decade, most suppliers had extra capacity,” Chrysler’s Chernoby says. “What we’re running into now – and it’s not just a local U.S. problem, it’s a global problem – many suppliers have no capacity. In fact, they’re struggling to meet the capacity the industry is asking them for today.”

Even if capacity isn’t an issue, there is a point of diminishing returns on piece price.

“On average, most suppliers will tell you the sweet spot for scale is 200,000-300,000 parts,” Thai-Tang says. “That’s a typical plant size, three shifts a day, six days a week.”

That means it may not be productive to share many parts across B-, C- and D-segment vehicles, as is targeted with VW’s MQB.

“If you’re going to bridge from B- to D-car, chances are (the part) is designed for the most stringent requirement, which is typically the D-car,” the Ford executive says. “You’re going to carry that design cost into your B-car. And if there’s diminishing returns on scale, is that the right thing to do?”

Another barrier is the sheer complexity of planning multiple products for several brands, targeted at global markets and engineered, produced and launched over a span of many years. Add to that mix automakers partnering on vehicle development, such as GM with PSA, Renault-Nissan with Mercedes, Toyota with BMW and Fiat with Chrysler, and the formula gets even more complicated.

Like automakers, the supply chain also will have to get manufacturing operations up to speed. “The OE can only be as flexible as its supply base,” Andrea says. “And the OE can only be as responsive to market changes as their supply base is.”

Hoffecker says parts makers will need to have global organizations and strong account management to compete, and the challenges may be too big for some, accelerating merger and acquisition activity in the sector. Global footprints are required to win, he says.

“For suppliers, the challenge will be aligning with the right platforms to begin with, because in this new world, if you don’t put your eggs in the right basket, you may wind up with a whole lot of broken eggs.”