Hello, my 2,73 differential was broken. I had it immediately replaced by the 3.73. now the car n vibrating at exactly 100 km / h and also at higher speeds. if I accelerate or take it away, it's gone. only at constant speed (example Cruise control). below 100 KmH no vibrations and from 120 again, now it generally makes whining noises again and oil leak , I have the third appointment in the workshop. because the seal is defective again! ... I have to say that this is not a cheap workshop and has consistently good reviews for tuning on Mustang. Whatcould go wrong there???