Need some quick help. At higher speeds of about 50 mph and more on highways. I feel an intense vibration from the rear of the car. Its more intense when I am off the throttle. At first i thought it had to do with the new driveshaft. But I recently had the car 4 wheel alligned yesterdayb/c of new wheels/susp. I also had the front wheels balanced "but not the rear wheels." I just put 19" Axis Wheels on the car. It also has Tein Flex Coilovers. My car is a 94 Lexus SC300 with a 2JZGTE and 6spd comversion.Thank you

The rears arent balanced?!? Well get them done. If you have a new responsive and tight suspension in then maybe it is magnifying simple wheel vibration from not being balanced.
If it still does it then worry

Ok I have progress, but still need help. I put my old lexus wheels on the car and I still have the same vibrations from the rear. This means it's not the wheels. Does this sound like a drive shaft problem. It had to be balanced twice already.