Toyota and Honda retained their positions as the automakers with the best relationships with their North American suppliers, according to a recent survey.

Michigan consulting firm Planning Perspectives Inc. released its 17th annual North American Automotive OEM Supplier Working Relations Index late last week. The study ranked the six largest automakers in the U.S. market based on responses from 652 salespeople from 108 top automotive suppliers.

Toyota and Honda have topped the rankings for years, according to The Detroit News, but General Motors moved up to third amid efforts to improve its supplier relationships and overall culture.

PPI President John Henke told the paper that companies with strong supplier relationships tend to receive new innovations, better prices and, as a result, stronger profits.

“They now have solid leadership at the top in global purchasing and supply chain who are committed to developing better relations," Henke said of GM.

Ford also showed improvement among survey respondents compared to 2016's report, but the Dearborn, Mich., automaker was still surpassed by its Detroit rival and fell to fourth place.

Fiat Chrysler, by contrast, declined compared the 2016 survey results but nonetheless climbed to fifth due to a sharper decline from Nissan.

Henke said the report reflected Nissan's efforts to secure the lowest prices from its suppliers. The automaker responded that the results "do not reflect our experience" with North American suppliers.