Steering wheel shake

I have a 2008 TRD Sport. All of the sudden last week truck started shaking when braking at speeds above 45 mph. Feels like a bad rotor, Had both replaced under warranty , they only had 2500 miles on them since being replaced. That did not fix the problem. Not sure what to do, kind of leaning toward something being wrong with the steering shaft? Seeing how there has been a lot of trouble with them, but have not seen where anyone has described having this problem when braking. Truck rides straight down the road, doesn't pull one way or the other. Just seems to do it when braking hard at faster speeds. Also it doesn't seem to do it as bad when braking going around a curve, almost like it binds something up and holds it from letting it shake. Any insight will be appreciated , currently truck really isn't safe to drive other than around town at lower speeds. Also everything on front end are tight and seem to be fine. I did recently change hub assembly on pass. side with one from bamatoy , have not done other side . Could that be the problem? It isn't making noise, or seem to be bad.

 

Check your u joints.

 

How much play should there be in the steering shaft? Is there a bearing where it goes thru the firewall? I can grab shaft in engine compartment and move it probably 1/4 inch in all directions.

 

is it only during braking? Sounds like bad rotors/pads.

 

It certainly feels like bad rotors too. I can't imagine have one warp within 2500 miles, then getting replacements and them being warped right out of box. I also went ahead and put new pads on with the rotors. Even though they only had 2500 miles on them.

 

Any Verdict?