I drive a 2004 Acura TSX with 61K miles. Up to this point, I've spent $1500 trying to fix the problem over the past 15K miles. I get not so good vibrations that appears at highway speeds. Here's what I've observed. Vibrating comes and goes at 64, 69, 73 and 81 MPH, +/- a few ticks. Can feel the shaking through the seat a little bit and definitely see the steering wheel shaking L & R. Doesn't make any diff whether I'm accelerating, decelerating, in neutral or clutch in. Doesn't make much diff whether on asphalt or cement roads. Shaking is less noticeable with full tank of fuel. Does not pull left or right. First appeared and became apparent quickly after a regular tire rotation and balance. Will continue to happen even after driving long distances. Does matter if it is 40 or 100 degrees outside. Here's what I've tried. 8+ attempts to balance tires at three different shops. Even tried 'Road Balance'. 2 sets of different tires plus a few one off replacements. None were worn abnormally, but were replaced to try to solve vibration. 2 alignments (which didn't show any misalignment). Replaced OEM wheels with new Enkei wheels with hub rings. Some proposed solutions. The axles have a bad inner CV. However, some people say only should shake when accelerating. Sticking brake caliper. However, all the brakes are wearing evenly and have plenty of pad left. Warped rotors that are causing them to be out of balance. The front rotors are slightly warped, but what Honda rotors don't warp. I get brake shuttering only at high speed braking and only at certain firm pressure/speed range. Sell the TSX and buy a Ford Mustang. Those suggestions are dismissed outright as crazy talk. I need help before I run out of money and hair.