I have a 2016 Mustang Convertible and the roof is sagging on the driver's side near the rear glass. I found "Technical Service Bulletin" 18-2036 which states this is common in 2015-2018 mustangs and it includes instructions on repairing the problem. It is a matter of changing two retaining clips on a tension rod inside the roof. It will need under $40 in parts. I brought the car to our local dealer and they are clueless or not interested in the job maybe because I made a claim with Ford headquarters to see of they may cover the repair as it appears to be common. Ford headquarters looked up my VIN and confirmed that this Servce Bulletin applies to my car. Has anyone had any experiences regarding this issue that they can share. Thanks