It vibrates 30 mph and up in whole car. Have front end done wheels and tires balanced 3 times, drive shaft checked and universal joints, brake guy said cant be caused by brakes, you can feel it in the wheel and in the seat. Please help me, thank you.I am a professional fire fighter. Les
Drive line vibration will be a much higher frequency buzzing-type vibration compared to a wheel's thump - thump vibration. The tires should be checked for a broken belt. Squirming in the outer tread is easy to spot but other things can show up that aren't so well-known. Anyone can spot a problem with a road force wheel balancer.
If you have cast wheels, Ford used to use a heavy locking lug nut on each one. Those needed a half ounce weight added to the wheel across from that nut to maintain wheel balance.