I bought a new F-150 Lariat and it vibrates like crazy. I've had it two months and it has spent 1 month in the repair shops. The service manager drove the truck on a test drive with me and confirmed it vibrates. He put it n Neutral and vibrations stopped. Has to be the Transmission. Transmission guy says nothing wrong. I've taken it to two ford dealerships and neither fixed the problem. I've owned two other F-150 both were smooth. Any suggestions?