docwyte

Have a vibration through the steering wheel when I hit the brakes, but only at highway speeds.

Brakes feel fine at all other speeds, which makes me think it's not a warped brake rotor issue.

Control arms maybe?

wrinkledpants

That would be my guess. I had a bad shimmy when I first got my CTT. Control arms helped a ton. Ended up being the DWS tires which were worn unevenly from the bad control arms that caused the rest of the shimmy. Control arms, alignment, new tires - butter smooth now.

wrinkledpants

Braking or coasting going downhill made it worse, for what it's worth.

PelicanParts.com

I'd start with the control arms and see if that makes a difference. Options here if needed. Here is a DIY if needed.