Mercedes Benz repair: 1999 WAGON, rear tires, driveshaft

Question
MY WAGON HAS JUST STARTED SHAKING IN THE REAR END. ONCE I GET TO 50 MPH IT IS FINE BUT OVER THAT STARTS SHAKING AGAIN.
I HAVE 132,000 MILES ON IT.
I JUST RECENTLY HAD IT ALIGNED AND IT DID NOT HELP

Answer
The first thing I would do is have a good and reputable tire shop inspect the rear tires. One of the rear tires could have a seperated belt or something causing this problem. If that is not the case, then you will have to inspect two different aspects of the rear end....Check the rear suspension to see if any parts are loose or worn and then check the driveshaft. If the driveshaft or any driveshaft components are bad, then that could cause a similar problem to the one you are describing.