DETROIT -- Tesla has cracked the ranks of top-performing automakers in a survey of suppliers that measures carmakers' willingness to encourage innovation and adopt new technology.
Tesla, appearing for the first time in the biennial North American Suppliers' Choice Study by Deloitte and Automotive News, ranked third, tied with Toyota and behind No. 1 BMW and No. 2 Mercedes-Benz. This year's survey ranks 15 manufacturers of vehicles in North America.
The survey showed that suppliers value their ties with automakers that encourage innovation, are willing to build relationships based on trust and are easy to work with. More than half the 170 suppliers that responded said they would withhold their most innovative products from automakers that do not participate in collaborative relationships.
BMW topped the survey for the fourth time in a row. Honda ranked fifth.
William Forsythe IV, a principal at Deloitte, said the landscape is changing "as the vehicle evolves from mechanical to more software-based."
"Suppliers are managing their relationships with OEMs differently than in the past," Forsythe said. "They're being selective about customers with whom they choose to do business."
Attitudes have shifted from the days when suppliers merely created parts from manufacturers' specifications.
Joe Vitale, Deloitte's global automotive sector leader, said suppliers often "have more knowledge than OEMs about customers. They're unwilling to add capacity unless it's going to add significantly to the value" of their businesses.
The survey measures automakers based on five factors: openness to new ideas, ease of working with the automaker, level of trust, willingness to provide financial incentives or rewards for supplier innovation, and ability to implement innovations. The factors are weighted according to their contribution to the overall index score. Openness to new ideas was the most important factor, accounting for 32 percent. Index scores are based on a 1,000-point scale.
Carmakers generally scored better this time than in the 2013 North American survey. The index score of top-ranked BMW increased 62 points, to 707 from 645, while Volks-wagen, No. 11 this year, increased 70 points, to 535 from 465. The average score rose 43 points, to 578 from 535.
Ford was an exception, sliding to sixth place this year with 583 points from second place in 2013 with 611 points.
As for Ford's Detroit 3 rivals, Fiat Chrysler slipped to seventh from fifth even though its score improved to 575 from 554. General Motors remained eighth even though its score increased to 555 from 511.
Suppliers gave Tesla high scores in openness, ease of working and trust. "Tesla is extremely aggressive, but takes a position that they are the innovator and will drive technology to the supply base," wrote one commenter, who added: "Could improve with a more collaborative approach."
Supplier comments on Ford were mixed. "Very open to recommendations but very difficult to get answers," wrote one.
"Excessive amounts of paperwork for product development. Working around in Ford computer system for purchasing, and logistics was extremely confusing," wrote another.
A third wrote: "Ford is quick to implement PROVEN technology but have been bitten by SYNC and are slower when it comes to unproven technology."
BMW again received high praise, finishing first in each category for the third straight survey in North America.
"BMW are a very experienced manufacturer and with stable long term development pace," wrote one.
BMW was praised for rewarding technical advancement and "has a clear process to do it quickly," wrote another.
Suppliers said relationships break down because of a number of factors. The biggest reason is because of inaccurate or inconsistent production forecasts, followed by management of design changes and management of change orders.
Poor relationships can make automakers less competitive. Most suppliers said they "withhold their most innovative products, competitive pricing and best human resources" from automakers that don't work collaboratively.
The study began in 2002 to research how automakers in North America and Europe support supplier collaboration and innovation. The study measures North American and European suppliers in alternating years.