Toyota, Honda and General Motors all raise their scores while Nissan, Ford and Stellantis again decline in Plante Moran’s 25th annual North American Automotive OEM-Supplier Working Relations Index (WRI) Study that evaluates relations between the Detroit Three automakers and their three leading Japanese counterparts.
The consultancy says Toyota, Honda and GM improved overall relationships “while managing unprecedented market volatility due to changing government policies, (electric-vehicle) program cancellations and the threat of new low-cost Chinese entries, uncertain sales volumes and continued tensions over cost-recovery issues related to materials and tooling.”
No.1 Toyota earns 386 points, up 18 from 368 in 2024 and its highest WRI score since receiving 415 in 2007. Honda rises 3 points to earn 347, its highest score since at least 2015. GM surpasses 300 for the first time, gaining 11 points to earn a 2025 score of 310. Plante Moran notes that 20 years ago, the automaker received only 114 points, the lowest WRI score ever recorded.
GM is “starting to turn the ship,” supplier relations analyst Angela Johnson tells Wards. “It’s long been said that in the auto industry, when the economy’s good, when the industry’s strong, everybody’s happy. But when it’s not, history tells us that OEMs revert to their embedded supplier management practices.
“And that stands out (in the WRI results) because history would tell you that, given the other three (automaker) declines that you would expect, GM might’ve joined them,” Johnson continues. “They didn’t – they went up. That tells me those behaviors are embedded and they’re going to last.”
Both Nissan and Ford fell 6 points from 2024’s survey, to 249 and 191, respectively, while Stellantis declined 11 points to remain in last place at 141. The 245-point gap between Toyota and Stellantis was the WRI’s largest since 2008.
Suppliers “perceive OEM behaviors – fairness, equity, accountability and then trust – through the impact of OEM decisions to their bottom line,” Johnson says. “What separates the top three from the bottom three OEMs is their ability to help suppliers reduce their costs to serve the OEM and manage uncertainty.”
The top three OEMs also “score better in the basics – communication, responsiveness, accessibility, engagement and buyer knowledge,” Johnson says: “These skills help suppliers operate more efficiently, and in turn, create strong relationships. Stronger relationships enable OEMs and suppliers to work together and better navigate industry uncertainty with more equitable risk and cost sharing.”
Dave Andrea, principal in Plante Moran’s Strategy and Automotive & Mobility Consulting Practice, says the automakers with higher scores show greater flexibility in their relationships with suppliers: “If you think about a new product or a new good, like software and electronics that haven’t typically been sourced, or are a new commodity/, new goods, then the OEM needs to look at how are they doing allocation processes.”
Andrea says interfaces were built over a century around castings and stampings and forgings and plastic molded parts, but he says now automakers have to take a step back and say, “‘Do all of our processes that we had for traditional products – do they fit this new supply?’...How (contracts are) written needs to evolve to this new supply base.”Plante Moran conducted the WRI study from mid-February to mid-April, receiving responses from 665 executives from 398 Tier 1 suppliers serving the six automakers with the largest U.S. manufacturing footprint: Ford, GM, Honda, Nissan, Stellantis and Toyota. The study tracks supplier perceptions of working relations with their automaker customers in which they rate them across the eight major purchasing areas, broken down into 20 commodity areas. The responses represent an estimated 45% of the six OEMs’ North America annual purchases.
