shaking

[twisted1]

ive got a big shake in the car from the 70 mph and up. ive had it alligned balanced rotated and 4 new tires but i cant figure it out and the dealership isnt helping me any.
heres the low down from 70 mph and up any day, any time, any temp, it starts to shake very violently like ur car does right before u blow a tire, but when i slow down it stops shaking as bad. any 1 have any clues, or ideas for me. thaks much.

 

[flrseclipse17]

i had a similar problem, i went and got new struts, brake rotors and pads and it eliminated it. dont know which one of those where the issue but i know that all where shot so.. maybe that helps.

 

[luv2rallye]

Try to isolate which wheel it's coming from. Does the steering wheel shake?

Shake each tire/wheel in and out hard from the front/back and top of the tire with the car on the ground to see if any ball joints are loose. Also bounce each fender up/down to see if suspension makes noise or is loose. Raise car off ground and grab each suspension member (sway bars, struts, shocks, tie rods,etc) by hand and try hard to move it all directions for looseness.

Another rare problem you might have that often goes unnoticed is a tire/wheel may be out of round (but balances perfectly). With tire off ground, place an object under and within 1/8 - 1/4" of the bottom of the tire (on ground). Now rotate tire slowly and watch if the distance between the object and the tire changes a lot. If so you have an out of round condition - then do same thing under both inner and outer rims to see if it's the wheel or not.