If it is making noise and grinding now, get your Service Manager to ride in the car with you.
Do whatever it takes to get them in the car with you.
When they hear it and experience it, they will have to do something.
They just can't sit around and wait for it to fail.
Even if they do agree that there is a problem, it will need to be documented
while your coverage is effective so the repairs will be covered.
PLEASE MAKE SURE THIS IS DONE.
IF THEY REFUSE TO DO IT CALL FORD CUSTOMER SUPPORT AND CALL YOUR FORD EXTENDED WARRANTY SERVICE.
Have you ever SERVICED the transaxle ???
The Owners Manual says it needs service every 30,000 miles,
but it really needs service every 12,000 miles.
If the service has NEVER BEEN DONE, they will have grounds to deny you the warranty coverage.