DETROIT - The increasingly murky timeline for the shift to electric vehicleswill require automakers and suppliers to become more transparent with one another as launch dates change and huge amounts of capital are deployed, executives and purchasing managers said.

The industry's electrification push comes amid higher interest rates, lingering supply chain issues and a shortage of labor, all of which have reduced profit margins for suppliers that are being asked to invest significant capital into new EV parts programs. EV sales growth, meanwhile, has slowed in the U.S., leading automakers to delay product launches, reduce production or postpone EV spending.

Executives throughout the industry almost unanimously agree an electrified future is inevitable, but how quickly that future arrives has become more uncertain in recent months. By delaying EV plans, automakers could make it more difficult for suppliers to get the returns on investment and efficiency they need to justify major spending for EV parts programs, executives and analysts warned this week at the Motor and Equipment Manufacturers Association's Vehicle Supplier Conference in suburban Detroit.

"It's difficult because, as we go to our investors and stakeholders, we are basically committing with our resources that we will get this kind of outcome, but that outcome ultimately can't be guaranteed," said Sandy Stojkovski, CEO of Vitesco Technologies North America, during a panel discussion. "At the end of the day, it's important to [have] a partnership approach with our customers."

Automaker purchasing executives at the MEMA conference vowed to be transparent with their suppliers and urged parts makers to be equally upfront with them as companies throughout the supply chain transition to EVs. Lisa Clark, vice president of supplier diversity, supplier risk and relations at Stellantis, said the automaker has been "very, very upfront" about its EV plans as it looks to find "long-term partners" in the supply base.

"There are some that have come forward and said, 'We're not sure we want to be long term with you. ... It doesn't fit with how we're choosing to move forward,' " Clark said. "And that's OK, because we'd rather have that conversation now openly and transparently."

Mike Lapham, vice president of procurement at Honda Development and Manufacturing of America, said the automaker has been focused on creating a "harmonious flow" throughout the supply chain, including by minimizing disruptions in vehicle assembly as much as possible. He said Honda expects suppliers to continue working on productivity improvements but is also urging them to come to the automaker with ideas about how it can become more efficient.

"We haven't been the best at implementing them in the past because of resource allocation," he said. "But with the constraints and challenges out there, we are very open to those ideas coming in."

Long term, the EV transition is likely to mean far fewer platforms and configurations on new vehicles, creating another change suppliers will need to navigate, said Mark Barrott, principal at Plante Moran. He pointed to General Motors as an example, saying the automaker plans to go from about 550 powertrain configurations on its vehicles today to 19 by 2035.

Mike Lewandowski, vice president of IT at metal components manufacturer Modineer, said simpler vehicles do not necessarily mean things will become easier for suppliers.

"It can be the inverse at times," he said. "If the car stays roughly the same size but with fewer components and fewer platforms, guess what? The parts are probably bigger and more complicated."

Suppliers also flagged labor as an area of concern moving forward, both as it relates to the availability of workers as well as wage pressures that are expected to increase in the wake of the UAW's historic tentative agreements with the Detroit 3.

Steven Blitz, chief U.S. economist at TS Lombard, said the U.S. population is aging, with workers older than 55 who have retired or left the work force. At the same time, there are fewer younger workers available because Generation Z is smaller than the preceding millennial generation.

Combine those factors with legal immigration levels dipping during the pandemic, and it's going to be harder for companies to find the workers they need. And with fewer workers and more competition from the new UAW contracts, labor costs are likely to remain elevated, economists at the MEMA conference said.

Vitesco's Stojkovski said it's been a challenge for the supplier, like others, to find enough labor for its factories in the U.S., and pinned part of that on too little legal immigration into the country.

"I really see this as a necessary next step to ensure that we're able to get the talent in all the different areas we need," she said.