Ford is finally adding Siri compatibility to its cars, with vehicles globally able to receive a software update to add Apple Siri Eyes-Free capability to their in-car systems.

Cars from the last four years are able to get the update as long as they have Ford SYNC 1.1 or 2.0 installed as the in-car entertainment and communications system. Owners are advised to visit or book an appointment with their local dealership to get the update.

Once updated, users of iPhones with Siri will be able to activate Apple's voice assistant with a long press of the voice-recognition button on the steering wheel. They can then use all of Siri's abilities, including making phone calls to contacts in their address books, set reminders, send texts and much more, all hands-free.

"SYNC was designed to be flexible and updatable, just like other mobile technologies, so our customers are able to get the most out of their smartphones while behind the wheel," said Sherif Marakby, a director at Ford.

"Siri Eyes-Free is another great voice-activated feature that not only adds convenience but helps our customers keep their eyes on the road and hands on the wheel."

Ford SYNC 2.0 is also known as "MyFord Touch".