When I go in the Interstate, i notice a slight shake in the steering wheel. The front tire tread seems to be wearing out more on the outer edges of the tire.
The steering is tight and responsive, so I am guessing there is something in the [---] that is linked to the [---]; and may need tightening or replacing.
Any ideas?

 

Could be worn out lower control arm rear bushings. Or worn out ball joints. The front suspension needs inspection.

Have no idea what you mean by (---) linked to the (---)

 

Also check your tire pressures too. Should be listed on the inside drivers door edge. These cars react a lot to the air pressures.

 

Could be inner or outer tie rod ends , or upper motor mount , intermediate steering shaft..

https://www.chevyhhr.net/forums/prob...problem-60373/

 

I the wear bumpy? Probably hubs.

 

Try to confirm or exclude hubs from suspects. It is easy.
if the hub is worn - this is audible.
I have changed hubs on my cars many times.
And so, I will tell:
If you hear a howl like a trolleybus (hey guys! Do you have trolleybuses in the USA?) Or a rumbling sound like from a light-engine plane - you suspect the hub’s premature death.
To make sure of this, you begin to load and unload hubs in turn. That is, the conversion from line to line and listen (turn off the music! Interferes!). If, when turning to the side, the suspicious sound amplifies, and when turning in the opposite direction, the suspicious sound disappears - your hub is on the way to the trash.
Now you need to determine which hub is dying. The sound is amplified in the right turn and disappears when turning to the left - the left hub dies. The sound is amplified when turning left and disappears in the right turn - the right hub dies. Of course, both hubs can die at the same time, but this is unlikely, I have not encountered this.
Control test. Lift the car to the car lift. With one hand, grab the suspension spring, with the other hand, rotate the wheel. No need to spin fast, do it lightly and thoughtfully. That hand, which rests on the spring, will feel light but distinct shudders. This ball from the bearing crosses bumps in its path. If you feel it, the last doubts have disappeared. Replacing the hub.

 

As a joke ...
There was a case when I felt a significant vibration quite unexpectedly. Everything was fine yesterday, but today my steering wheel beats like the demon infused it.
I thought it was a big problem. I need to somehow get to the house and diagnose the suspension, then look for time and money for repairs. And the risk of being left without wheels for a few days is a terrible prospect.

The real reason? The day before I washed the car. Outside, it shone like an Easter egg. A stream of water hit the inside of the wheels. The thick layer of mud got wet and softened, but not washed out. The dirt just slipped into the bottom of the wheel and froze there overnight. Thus, in the morning I received heavy clay-ice weights on my front wheels, which I could only get rid of in the evening after removing the wheels and a few minutes of working with a hammer and steel brush.

 

I actually had that happen one winter

 

Tire pressure won't make the tire just wear on the outside of it.
There is a front end issue causing it.
Tires that are cupped do to not being in balance for many miles can cause the high speed vibration.
Worn front end parts can cause it also.
Just a bad strut shock could make it happen.
If the wheel shook side to side I would look more into steering linkage or bent wheel.

 

Hubs make noise.
Won't make the tire bumpy.