DETROIT -- Ford Motor Co. on Wednesday said it's extending the warranty on certain 2014-16 model year Focus and Fiesta sedans with dual-clutch transmissions by two years and 40,000 miles and offering a software update for customers who continue to have issues with the problematic gearboxes.

The automaker said it was extending the clutch warranty to seven years or 100,000 miles in the U.S. and Canada for those 2014-16 model year Focus sedans and 2014-2015 Fiestas, matching previous warranty extensions for some older cars. Warranty coverage for the transmission control module remains 10 years or 150,000 miles.

Ford also said it will reimburse customers who are now covered with the extended warranty who have paid for clutch repairs out of pocket. The automaker said it recently saw an uptick in out-of-pocket expenses for 2014 model year customers whose warranty had recently expired.

"While these vehicles always were and remain safe to drive, we regret the inconvenience our customers have experienced," Dave Filipe, Ford's vice president of powertrain engineering, said in a statement.

Filipe said the warranty extension will cover about 560,000 customers. The automaker did not disclose any cost estimates, but said it will be reflected in third quarter earnings.

It said about 165,000 owners, about 16 percent of the original customer base, still need a free software update. The update provides an enhanced warning if a transmission control module fails.

Ford said, where necessary, it will repair the module up to 6 months after the 10 year/150,000 mile warranty has expired.

The automaker says tests show Focus and Fiesta sedans built since the second half of 2015, along with earlier models that have received software updates, perform well.

Ford has been haunted by the transmissions, codenamed DPS6, since they were introduced in 2010. Thousands of customers complained the transmissions would shudder, jerk and hesitate.

Litigation is ongoing.

Ford in 2014 extended the transmissions' warranty by two years and 40,000 miles for 2011-2013 model year vehicles. Since its inception, Ford has issued more than 20 technical service bulletins related to the gearboxes.

The National Highway Traffic Safety Administration said Wednesday it has reviewed recent complaints about the transmissions but has found “no evidence of an unreasonable risk to safety,” adding it will continue to monitor complaints and take action as necessary.

The automaker last month told its U.S. dealers to give free repairs to any Focus and Fiesta owners who complain about problems with the cars' PowerShift dual-clutch transmission, according to a memo obtained by Automotive News.

The memo, first reported by the Detroit Free Press, followed a July 11 report by the newspaper that said Ford knew about the transmission defects yet sold them anyway. The automaker responded to the report last month, saying it made "conclusions that are not based in fact."