Can't get it over 50 or 55 without the whole rear end shaking me off the road. I changed shocks and sway bar links, and it didn't help the problem. I need help with this issue please.

needed shocks and struts was told by tire store that its a common problem with this model the cost was estimated $534.00. I returned to previous owner the way I got it all shook up

Hi my name is jonathan and i drive a 1997 infinity qx4 really nice car. Only 1 problem and its a problem that i tried fixing and still don't no what it is. The car shakes horribly from the rear like it wants to lose control. i cant drive it on the highway at all. i bought new tires, alignment, took it to many mechanics and they don't know whats wrong with it. they say everything looks good. Any one know what it is, i need this fix ASAP before i end up dead because of the way it drives.