Modern manufacturers are taking a cue from the Model T and making some vehicle seats from soybeans.

The Model T Ford once contained 60 pounds of soybeans in its paint and molded plastic parts, according to Ford.

In new Mustangs and other vehicles, Ford Motor Co. uses soy-based foam — instead of petroleum-based products — in the seats, and John Deere tractors soon could have soy seats as well.

"It's good to be green," said John Koutsky, vice president of product development for Sears Manufacturing Co., a major seat supplier to Deere and other companies. Sears, based in Davenport, Iowa, is using Ford technology to work with Deere to develop soy-based foam for seats on Deere farm and construction equipment.

Today's manufacturers are looking for ways to replace petroleum-based products with ones made from crops, as the political, environmental and economic costs of oil grow.

Soy is often cheaper and more environmentally friendly than petroleum and comes from a renewable agricultural source, said Larry Johnson, director of the Center for Crops Utilization Research at Iowa State University. Soybean components such as oil and protein are used in hundreds of products, as diverse as biodiesel fuel, adhesives, plastics, paint and paper coatings, Johnson said.

Deere, based in Moline, Ill., already uses soy-based materials for parts such as hoods, side panels and doors on some models of tractors, combines, cotton pickers and backhoes.

Soy oil replaces some of the petroleum chemicals usually used to make seat foam, Koutsky said. A complete seating system, including suspension systems, will be about 20 percent soy oil, he said.

Sears expects commercial production of the soy seats by next year and plans to use soy foam across its product line. The company makes seats for other makers of agricultural, construction and industrial equipment and for manufacturers of heavy trucks such as Freightliner and International.

Sears' work on the soy seats includes developing processes to assure that the seats will be waterproof when used on equipment without a cab for the operator, Koutsky said. The foam also must meet specifications for support and feel, matching materials made with non-soy material, he said.

Ford, based in Dearborn, Mich., began research on soy foam in 2001 and developed the product with seat supplier Lear Corp. of Southfield, Mich.

Odor was one problem to overcome, said Cynthia Flanigan, a Ford plastics technical expert. The soy materials had a rancid smell that would be unacceptable in cars.

Researchers found a way to strip away the odor-causing components, Flanigan said. The foam first went into new Mustangs delivered to showrooms in August.

Jim Bintner, general manager of Charles Gabus Ford in Des Moines, Iowa, said the soy foam works great, giving seat cushioning the same feel as traditionally made foam.

And the smell?

The new Mustangs "smell great," Bintner said. "They smell like any other new car on the market."