vibrations

Tires are known to shake when they have a broken or loose steel belt, and can do it at very specific speeds on certain road surfaces. Let a shop spin balance the tires and tell them you are experiencing a shake at a specific speed. Again, if the shaking starts at the same speed, it's the tires. Lots of info at this link: souzastireservice.com/tires-101/shakes-and-wobbles.aspx

What year Forester? If this car has a CVT the transmission could be at fault.

My forester is Year 2000

Could be lots of things, like a contaminated inner joint on an axle (DOJ), or even a simple blown tie rod end, ball joint, or broken swaybar link. I've seen them all result in idiosyncratic vibration.

No CVT in 2000. Take Ernie's advice.

There's also a small chance that you have a front diff bad pinion shaft bearing.

I have a 2014 forester steering vibrations at highway speeds. I only have 47k miles!! Took it to the shop and they found it to be the lower control arm bushings worn out left and right side. It was still covered under warranty!I am not an aggressive driver at all. My concern is, is this going to be an issue every 40-50k miles? I guess I’ll just have to cross that bridge when I get there!

How you solve this issue

Replace the control arms.

My subaru forester is 2016. This only started after car had tires rotated and all alllignment completed. Any other suggestions?