Toyota Motor is one of the conspicuous success stories of Japan's radical efforts to revive its economy, with profits rebounding and its 60,000 workers in Japan hoping this year to receive their first base wage rise in six years.
But when the carmaker reports on Tuesday quarterly profits that are likely to be nearly five times what it booked a year ago, its continued revival will mask a much less optimistic mood among the auto industry's smaller firms.
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For them, the reflationary economic policies of Prime Minister Shinzo Abe, dubbed "Abenomics", have failed to trickle down beyond the big carmakers, which are actually continuing to squeeze their networks of suppliers.
Pay rises are the last thing on their minds.
"Behind the recovery at the big carmakers is their pressure on suppliers to cut parts prices. It's been hitting us like a body blow," said a senior executive of a company that makes drivetrain-related parts for a major Toyota supplier.
At this small company based in Aichi prefecture, home to Toyota and much of its supply chain, orders have yet to recover from the global financial crisis, and profitability has actually fallen. Operating profit margin has fallen to below 2 percent from around 5 percent in 2008, largely due to pressure to cut parts pricing, said the executive.
Like other suppliers interviewed for this story, the executive declined to be identified for fear of jeopardizing the firm's position in Toyota's supply chain.
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Toyota did not comment on details about pricing and cost arrangements with its suppliers.
Its president Akio Toyoda has acknowledged that "there are expectations on Toyota" to pass on the benefits of Abenomics to its workers, but he has not clarified how that would be done.
Toyota is under political pressure to raise wages as its union is set to demand a 1 percent base pay rise, which would be a modest hike by international standards but represent a watershed for Toyota workers who earn less every month on average now than they did a decade ago.
However, a Toyota wage rise would not necessarily represent a triumph for Abenomics - a mix of fiscal spending, economic reform and monetary stimulus designed to pull Japan out of a decades-long slump - in the broader auto industry.
Lower down the supply chain, many companies, especially the smaller ones, are unlikely to be able to raise base wages, partly because of the price and cost-cutting pressure. And given that the minnows of the industry account for the bulk of its jobs, that could be worse than a zero-sum game.
"Polarisation between large automotive parts-makers and smaller ones is likely to intensify because the big ones have the resources to take their business overseas and the smaller ones don't, and this could also become more evident in employee salaries," said Seiji Manabe, professor at Yokohama National University and an expert on automotive suppliers.
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Haves and have-nots of Abenomics
To be sure, the fruits of Abenomics are trickling down below the carmakers, to some of the biggest or most technologically advanced parts suppliers which are making innovations and riding high on the wave of surging profits in the auto sector.
But the virtuous cycle of Abenomics - rising wages, prices and spending - is a stranger to the smaller companies.
Japanese parts manufacturers employ 612,000 people, almost four times as many as carmakers and motorbike manufacturers combined. Workers involved in the auto industry in one way or another are estimated at 5.48 million, about 9 percent of Japan's working population, according to Japan's auto lobby.
Rengo, Japan's top labour federation, has called on its member unions for an minimum 1 percent base wage rise.
The Toyota union, which is covered by Rengo, is set to ask for a rise of 1.1 percent, or 4,000 yen (£24) per month, in the average base salary for Toyota workers, in addition to bonuses totalling 2.4 million yen and an incremental pay rise.
For Toyota, a 1.1 percent wage hike for an estimated 240,000 Japan-based employees, including its group companies, would add around 11.5 billion yen to its fixed-cost base, though this would be a tiny fraction of the 880 billion yen in additional operating profit that the global business expects to make in the year to end-March.
The company spent years relentlessly cutting costs, a trend unlikely to be reversed, and it also demands price-reduction on suppliers every six months, which generally run at 1-3 percent, industry sources said.
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Under a drive launched in 2012 to make its cars more competitive, Toyota is boosting use of standardised parts. Toyota says its intention is to introduce better functions across a wider range of models, and cost cuts are just one of the many means of improving its vehicles.
According to individuals familiar with the situation, this means Toyota is giving larger chunks of business to a smaller number of suppliers, and it is asking for cost cuts of 30 to 40 percent for some parts - in certain cases double that level.
A senior executive at a parts supplier for Toyota said the Aichi-based firm had managed to cut costs by 40 percent for some parts by redesigning products and switching to cheaper imported materials, and so far that made it more competitive.
"The question is whether we accept an even bigger cut. If we do so, then that soon becomes the norm, even if we are bleeding in dire red," the executive said.