Q: Grinding/popping sound when turning wheels all the way and slight shake in steering wheel/pedals under acceleration.

My 2008 Volvo C30 was having a shaking problem during acceleration. One shop told me it was the right cv Axel. So I fixed that and it stopped for about 30 miles till it vigorously started shaking at 80 mph and ripped me to the right side of the road, as I was slowing down I heard a rotational grinding sound. Took it to another shop, he said he couldn't find anything wrong with anything other than the left cv Axel so he said it was worth a shot. Got that fixed and boom, it drove great. Drove for about 100 miles and then the exact same thing happened. I let it cool down for about and hour and miraculously it could drive smooth again but after driving for about another 100 miles it happened again. Now, I can't get away with driving 25 miles without feeling a slight shake in the steering wheel and gas/brake pedals when accelerating and slowing down. I have no idea what it could be because everything is in good condition on my front end. Could it be low power steering fluid? Wheel bearing?

My car has 120000 miles.
My car has an automatic transmission.