Pontiac Repair: car shakes, tie rod end ball joint, free diagnosis

Question
Pontiac Grand Am 1995

When accelerating at higher speeds 55-65 mph the car starts to shake and sometimes if you race the motor it will stop for a little bit.  

Car drives fine around town but this happens when on the highways.  

Answer
I'm guessing that when you say "race the motor" you are taking the transmission out of gear and revving up the motor. First thing to have checked is the tire balance on all 4 wheels. A back tire may be causing this. Yes back, if it was a front tire the steering wheel would shake and you would feel this looooong before highway speeds. If that isn't it then you may have a bad tie rod end , ball joint or wheel bearing. My personal thought would be that you have a bad front axle though. When you take the load off the drivetrain it will cause the axle to come back into the correct alignment and not shake anymore. Also if you do have a bad axle then make certain there isn't a further cause for this such as a bad motor or transmission mount. All of these things can be checked for you by a trustworthy mechanic and most shops offer a free diagnosis. If you don't know a good shop, ask around and go to more than one so that you can get second opinions. Hope this helps and good luck!