He would not discuss details and said the companies "hope to announce a definitive agreement soon."
A Ford spokesman said: "We always talk to other companies including GM." He declined to elaborate.
The New York Times today reported that the companies plan to jointly develop automatic transmissions and are considering a manufacturing alliance.
GM and Ford are playing catchup as other automakers hit the market with gearboxes ranging from seven to nine speeds.
Chrysler Group, through a joint venture with ZF Friedrichshafen, offers an eight-speed automatic in the Chrysler 300 sedan and the 2013 Ram pickup. It is also planning to offer a 9-speed automatic transmission licensed from ZF.
Audi, BMW and Lexus offer eight-speed gearboxes, while Mercedes-Benz offers a seven-speed.
Mike Omotoso, powertrain analyst for LMC Automotive in suburban Detroit, says the main benefits of adding more gears are fuel economy and refinement.
"The engine has to do less work, so they aren't revving as much as they used to with fewer forward gears," he said.
The partnership expands a transmission alliance dating to 2002, when Ford and GM agreed to work together on a family of six-speed automatics for fwd vehicles.
The transmissions, including the Ford 6F and GM 6T70, have been installed in millions of vehicles including the Ford Fusion and Escape, and the Chevrolet Malibu and Cruze.
Ford and GM appear to be altering plans for eight-speed transmissions with an eye toward the greater savings that could come from more gears, one of the sources said.
In June 2011, Ford announced plans for its own eight-speed automatic, but did not specify an application. The company has said little about the transmission since. Some news outlets reported it will be designed for the F-150 pickup.
One of the sources with knowledge of Ford's plans says the company scrapped a homegrown eight-speed transmission program within the past year, before it began working with GM.
Last year, GM CEO Dan Akerson said that GM would spend $204 million to equip its Toledo powertrain plant to produce a homegrown eight-speed transmission. He wouldn't say what vehicles it would go into or when it would reach production.
Two sources said today that the eight-speed transmission is on track for a mid-2014 launch and likely would go into at least one Cadillac vehicle, likely the next-generation CTS sedan, and eventually GM's pickups and SUVs.
But one of the sources said that GM has reduced the volume projections for the eight-speed.
Said the person: "That rear-drive eight-speed is likely to be very, very low volume now."