Ford on Tuesday extended most of its incentive offers on Ford-branded vehicles until September 30 and enhanced deals on five models, Reuters reported.

The news agency said Ford's incentives - including its Lincoln and Mercury brands - averaged $US3,687 per vehicle in July, a 5.8% increase from June yet, despite that increase, Ford's sales fell 11.5%, due to lower fleet sales, weak car sales and the change over to a new version of the F-150 pickup truck.

Most of Ford's vehicles are already offered with zero-percent financing for up to five years or $3,000 in rebates, Reuters added.

According to the news agency, Ford's tweaks include lower interest rates for the Mustang, Escape and Explorer Sport Trac and a $500 increase in rebates for the Taurus and Escape, while the high performance Focus SVT model will now be sold with the same incentives offered on other Focus versions.