Shimmy shake between 60 and 80 mph
 

I'm thinking it's the tires but are there other possibilities? It's not so bad that it's scary but it is annoying.

Thanks

Is it in the steering wheel or your seat?
Steering wheel means front, seat usually means rear.

Have you gotten your tires balanced lately? How old are your tires?

It could be a number of things honestly. Usually the biggest case is wheel balance at that high speed range. Or bad tires. One or more of them could have a separated belt.

Also check your lug nuts, scary to think about, but they may have come loose.

This happened to me once and is definitely something to check in this case.

Also simply look to see if a wheel weight was thrown. See if tires are wearing evenly, or excessively. That can throw off balance enough if everything else is still a-ok.

After those simple visual checks, next step in diagnostic is usually jack up each front a-arm and then grab wheel at 3 and 9 o'clock and try to move the wheel in/out, and then again at 12 and 6. can help you find a bad bearing, loose suspension component, etc.

Other possibilities include bent rims, loose control arm bushings, tie rod ends or ball joints, a bad strut mount (unlikely), car out of alignment, chopped or bumpy tires (caused by worn struts), warped rotors or snow/ice packed in the rim causing imbalance.

when I bought my ES300, all 5 on all wheels were 'hand tight' .. at best.

Shake is in the steering wheel.

I just recently redid the brakes so I'm sure all the lug nuts are tight. It was doing it before the brake job tho.

Guess I'll take it to a tire store and have them check the balance and tires.

Thanks

It can be a few things:
- loose lug nuts
- wheels not balanced
- seized brake
- bad ball joint
- other loose suspension components

Bad Master Cylinder
 

My car was doing same thing. Brakes were dragging after about 15 minutes. Changed calipers, rotors, pads. No change. Turned out to be a bad master cylinder. Jack up back of car. Start it. Don't touch the brakes. Wait about twenty minutes and see if you can spin the rear tires, if not you probably have a bad master cylinder. Make sure hood is closed. Good luck.

Could it be where you are driving? I know some roads around here will make me feel like I'm getting a blowout at times.

If you have new michelin premiers they definitely amplify road shake in the steering wheel at first though they've definitely improved after the first 1000 miles.