I know that 99% of the time this is caused by wheels or tires. But I have had them tested and balanced 4 different times at 4 different places. Took it to chevy dealership and they said its the suspension and wanted 2k to replace it. I said no thanks and bought and replaced the front shock assembly and cv axels just in case and new brakes and rotors. but now the shaking happens from 60 -65 so I definitely affected it but just moved it to another speed range. any thoughts on what could be causing the shaking? I plan on replacing the rear shocks and springs over the weekend because they do appear too springy and I'm betting they need it as well.