I have a 99 Aurora (same suspension as cadillac cars and bonneville etc) and cannot get this car to stop shaking! Its getting progressively worse too. I've been all over the net searching, does anyone know what it is? Just had my tires RFB'd again for like the 7th time, tires have 5k on them, Kelly Charger GT 235 60 R16s. Its the usual, 65+ shake in the floor, not the wheel, that also comes and goes at the same speed.
Im at wits end! Recently started doing it at 30+.
Please anyone help!