BIRMINGHAM, Mich. — In 2026, supplier relationships got better for all six big North American car companies, even with tariff issues and the high costs of electric vehicles, says Plante Moran’s yearly Working Relations Index study.
The 2026 North American Automotive OEM-Supplier Working Relations Index study showed that all six major manufacturers improved for the first time in the survey’s 26 years. Ford, Toyota, and Stellantis had the biggest improvements.
The results show the effect of four main trends. The WRI scores suggest that tariffs and electric vehicle cost recovery changed how suppliers see fair business practices. Since purchasing teams couldn’t control how much their car companies paid for these costs, they focused on improving the parts of the relationship they could manage. These efforts were also helped by rules to return to the office and tiredness from constant crises.
Ford had the largest increase in WRI scores this year, going up 32 points. Toyota went up 23 points, and Stellantis went up 22 points. Honda added 13 points, General Motors went up eight points, and Nissan improved by six points.
Even with these gains, the ranking of the manufacturers stayed the same as last year. Toyota and Honda are still at the top, while Detroit car companies showed some of the biggest improvements.
Toyota scored 409 points, going over 400 for the first time since 2007 and reaching its second-highest score ever. Honda got its highest score since 2007 at 360 points, moving into the study’s “good-very good” category.
General Motors got its highest WRI score ever at 318 points, but it fell further behind Toyota and Honda. Nissan went back to its 2024 score of 255 points, its highest since 2014.
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Ford reached 223 points, its second-biggest increase in WRI history. Stellantis got 163 points, its best score since 2021 during leadership changes and efforts to improve.
The study said the improvements were important because of the “trust gap” found in the 2025 survey, which showed growing differences between the highest-rated and lowest-rated car companies in trust.
“In 2026, all six car companies improved trust scores by communicating better, being easier to reach, and solving problems more effectively,” said Dr. Angela Johnson, a principal in Plante Moran’s automotive and mobility consulting practice and head of supplier relations analytics. “Also, in the 10,000 supplier comments we received — more than three times the number from previous years — we saw a growing shared understanding that working together is the best way to handle constant crises, innovate, and grow.”
The improvements were mostly because suppliers felt better about long-term profits, fair business practices, buyer performance, and communication, according to the study.
Toyota stayed the leader in supplier confidence about long-term profit chances, while Ford, Stellantis, and Nissan made big gains.
Ford and Stellantis had the largest improvements in fair business practices, while Toyota and Honda led in helping suppliers cut costs. GM made the most progress in covering sunk costs and electric vehicle cost recovery but was criticized for its supply chain strength efforts.
Buyer availability, involvement, and quick responses also got better. Supplier ratings of buyers’ ability to fix problems improved across all manufacturers.
Toyota and Honda stayed ahead in communication and trust, though Ford and Stellantis made the biggest gains. Ford purchasing executive Liz Door had the largest improvement in trust among purchasing leaders.
“Suppliers seemed to recognize the efforts car companies made over the past year to control what they could and to help suppliers deal with industry uncertainty,” Johnson said. “Even if suppliers didn’t get their ideal result, they gave credit to the car companies for taking their meetings, listening, and taking action.”
The survey results also showed the importance of what Johnson called “controllable” behaviors — actions that connect purely business-focused and relationship-focused interactions.
Johnson said the main differences between the best and worst-performing car companies were what she called the “Six Cs”: fair business practices, consistency, clear expectations, communication, continuity, and teamwork.
“The WRI Study suggests a growing focus on how organizations behave,” Johnson said. “And the benefits go both ways.”
This year, Plante Moran also looked at responses from the top 50 North American suppliers separately to find other trends.
Those suppliers gave better ratings to all six manufacturers, matching the broader survey group. However, the results also showed long-standing cultural views within the industry.
The top 50 suppliers rated Nissan, Honda, and Toyota higher than their overall averages, while rating GM, Stellantis, and Ford lower than their averages, especially in trust, communication, and profit chances.
“Organizational memory is very long,” Johnson said. “The Detroit Three are still working to overcome the cultural habit of traditionally adversarial purchasing organizations.”
Toyota’s more careful electric vehicle strategy also seemed to reduce business pressure on suppliers, while GM, Ford, Stellantis, and Honda faced more supplier impacts related to electric vehicle write-offs.
