Hello there, So I have an FX 35 RWD. Shakes (steering wheel back n forth) fairly bad, getting worse i'd say, when braking Noticeably at highway speeds its bad, during side roads n slower speeds you can still feel it in the steering wheel and the car. Took it into a pep boys they measured everything from pads.. rotor.. tire balance, and everything was in spec and great condition so they came up with that my steering knuckle could be bent slightly or possible 'dog trackin" issue. Could the steering knuckle cause such a shake? Is there anything special I have to do to replace it. Thinking about doing it myself ($250 for labor a local shop) if possible just don't know if i can if i need to pull a bearing out or replace a bearing if i need power tools ect. Thank you for the help!

Hi and welcome to NICO Club!

I'm not sure I agree with their diagnoses. It differs from your symptoms. Something loose would have play and shake. Something bent would not shake, just be bent over into a different position. Alignment, wheels and tires, brakes and suspension, and the steering system could be a culprit. Supposedly they inspected the stuff that needs inspection so maybe get a second opinion elsewhere.

Potential causes that come to mind:
Bent Rim
Unbalanced, out of round tires
Warped rotor
ABS actuator needs adjustment (caliper drag)
Brake caliper is partially seized
lower control arm bushing is shot
tie rod bushing is shot
wheel alignment is out of spec
damper is blow

For a job like the steering column work, you'll want to use the FSM (factory service manual). Here's a link to each chapter. Start with "FWD" for the table of contents. "PS" is the power steering chapter. I'd look for play in the column or visibly bent parts before taking something like this apart. You don't want to do this work if you don't have to.
http://www.nicoclub.com/FSM/FX/2005_FX45-35/