NEW YORK — A day after the National Highway Traffic Safety Administration said it will require manufacturers to make all parts for all vehicles at once, the auto industry is saying that is just not realistic.

The U.S. Auto Parts Council, which represents about 70,000 auto parts manufacturers, said Friday that it will launch a pilot program this month to ensure that manufacturers can meet that deadline.

“We’re not going to go down to the automotive supply chain and say, ‘Okay, we have to make everything together in a single step,'” said Mark McInerney, the council’s president.

If the goal is to get all cars to be 100% automated, “then we need to make every car as fast as we can,” he said.

McInerneys group is working with Ford Motor Co., General Motors Co., Toyota Motor Corp., Honda Motor Co. and others on an automated-parts initiative.

But auto makers have repeatedly said they won’t make cars entirely automated and said they’re going ahead with major overhauls in the coming years.

It’s been a year since Ford announced it would replace about 1.2 million of its 4 million vehicles with software-controlled automated systems, a milestone it says will cut fuel consumption by half and cut $8.6 billion from fuel costs by 2020.

Ford has also pledged to spend $100 billion over the next decade to make its vehicles more fuel-efficient and to install more advanced safety systems, among other initiatives.

Last month, GM said it would spend $4.6 trillion on its fleet of vehicles by 2020, more than any other automaker.

And Honda, which is developing an autonomous system for its vehicles, said last month it is expected to spend a total of $4 trillion over the life of its vehicle fleet by 2021.

Automakers are also moving to upgrade their existing fleets to software that automatically detects if the vehicles are in an accident and shuts down the engine, brakes and steering.

In its regulatory announcement, the NHTSA said the goal of the pilot program would be to “deliver a 100% automation of vehicle manufacturing, including the automated assembly of components, by 2022.”

In addition, it said, the goal will be to implement a program that allows auto manufacturers to quickly assemble and test vehicles on their own site, while the rest of the industry has to continue to produce vehicles at factories that must be located in a factory in another country.

Still, McIners group said in its announcement that it would be taking the next steps “in order to accelerate the transition to an automated manufacturing environment.”

We’re taking steps right now to ensure the safety of our members, our customers and the millions of people who depend on them for their jobs,” he added.

He said the group will provide a summary of the program to the federal government, which will then decide whether to approve it.

Auto-parts makers say that will be a tough task.

GM Chief Executive Mary Barra, for example, said in March that the auto-assembly program is not yet ready to be rolled out.

Barras company plans to move ahead with the pilot by the end of this year, she said in an interview.

For many manufacturers, the pilot project will be difficult, McAsterney said.”

What’s the point in putting a whole new technology on a vehicle?

What’s the benefit to the customer?” he said, adding that the new systems are expensive to install.

However, GM and Ford said in their regulatory filings that they are moving ahead with plans to upgrade existing vehicle fleets to automated systems by 2021, and to put the program on hold until the end