According to reports, some valves on the base of the hydraulic drive of the rear fender will start leaking liquid, which can then drip to the exhaust and cause a fire. Ford reported that one GT in Germany had already caught fire, but luckily no one was hurt.
The feedback will affect the models made from December 20, 2016 to July 31, 2018. Ford added that the issue seems to be because there are cases where there is too much pressure in the hydraulic valve block below the wing which causes some liquid to run.
The fix is likely to be a software update to prevent the system from applying too much pressure. Some models may also need a hydraulic check valve, filter and O-ring.