Subaru Repair: shaking and noise, outback legacy, subaru outback

Question
Hi Frank,
my subaru outback legacy wagon 1997, shakes when I hit 50+ mph. I took it in to the dealer in culver city and they check the wheelbearings, and said they were fine.  They told me I need new tires and an alignment. However my tires have lots of tread left, I looked carefully!  
What steps would you advise I take in this problem.  I don't trust the dealer because everytime I go there they won't let me speak to a mechanic, just an inbetween sales rep.  They also some how find a thousand dollars worth of repairs every time I go in.  

Answer
Hello Scott,

     As being one of those technicians I know what you mean. I don't know about other dealers, but we always check over your car when you bring it in even for an oil change. Sometimes thats good, and most of the times it's bad. LOL  Just kidding.  To answer your question, it does sound like your tires. First thing i would do is have all 4 tires balanced. (any garage can do this). When they balance them also ask them to make sure there isn't a broken or shifted belt in the tires. This would also cause a vibration and should be replaced.       I hope this helps.

                                    Thanks,
                                       Frank