have someone drive next to you and look at the front and rear wheel then move and check the other side. there are about 30 things your car could be doing this and most have probably been covered. if its a wheel or suspension it will be obvious. that doesnt mean thats a problem, it means youve isolated the trouble to front or rear and maybe left or right.
usually suspension problems that arent normal to wear wont be noticeable without the load on them so freewheeling the car on a rack wont help. seen a gm trans do this in a cavalier, but it was a vibration not a shake or shimmy.
Hi sorry you spent so much .. but my opinion is tire balance.. A tire out of balance well start shaking the car at about 30 to 40 mph.. if the whole body shakes then it is most likely a rear tire. if the steering wheel shakes more then its a front tire.. or even a bent rim..
good luck
tim
Getting a vehicle properly diagnosed is the best way to avoid all these unneccessary costs to replace things that were obviously okay. Find a shop and mechanic that knows his or her stuff and get them to road test it with you. Find out if they want to get to the bottom of it or if they just want to quickly replace something to get you out the door. I know this is a tough and frustrating problem.
Did you check the transaxle mounts? They could be lose/broken.
Ok I have an 01impala 3800 series 2 I have had an issue with it shakeing so I replaced the breakes rotors and shocks and struts every mogor and trans mont bough new tires and the shakeing got worse ive taken it to 5 different shops all of them say it could be something in the axel so I replaced the both sides and the shaking is still there ive put about 2300 dollars into trying to fix this but nothing works im at my witts end and wanna push the thing off a bridge please help shake will only happen above 30 then gets more violent as I accelerate
