I think the shakes are a common problem on aging 4th gens. And I think we've ruled out wheel balance (because people have gotten the balancing done with no improvement) and obviously wheel alignment. I've heard "tie rod ends" which makes sense, but I haven't seen any posts where somebody has gone out and done it, and reported the results.

What I observe on my own car, is that on the 4 Sumitomo HTR+ (235/40-WR18), the right front has worn almost to the point of the tread wear indicators, while the other 3 are ok. I have rotated religiously FYI. So that leads me to believe that something with the right front suspension is causing the shaking which is bad at about 50-60 mph. At 80 it becomes far less noticable. Does this observation tell anyone what it might be?

From my own experience, on a RWD Volvo, it takes replacement of bushings and tie rods to fix the shakes, and it is so expensive that the owner needs to consider living with it. I'm curious if a Maxima nearing 100k is the same way? I mean it's not worth $1000 to fix this annoying problem!