front shimmy when apply brakes

Hey guys, I got an issue with my 1999 C1500 2wd pickup I hope to be able to get some help on.

Truck shimmys when I apply the brakes at 50+ mph. When I say shimmy I really mean shakes alot.

The steering wheel has about 2 inches of play.
Truck tracks good when I let off of the wheel at speeds.
I have replaced both rotors and brake pads on the front. All bearings have also been replaced on both sides of the rotors.

I took it to the alignment shop but he said it did not need aligned.

He said it seems to be a problem with the power steering pump or gear box? Not real sure this make much since. He also said he does not think it is getting enough presure to the gear box when under load.

Not real sure if this would be correct or not.

Myself I was thinking tie-rod end but he said they look ok as well.

Any suggestions as to how I would verify what the part/problem is prior to start replacing items?

Thanks Troy

Check for play in the gear box and any steering component, new rotors still cause this if the mounting surface on the hubs weren't true and rust free when the rotors were replaced. Rotor runout should be checked with a dial indicator and be less than .003".

New rotors can be warped and I have seen this happen.I have seen new rotors warped so bad tht they had to be sent back for another set of new rotors.

I too have seen new rotors that are warped. The last set I got it was suggested that I have them turned to true them up before I put them on. At the time I thought it was a foolish suggestion as they were brand new (an we all know that new parts are perfect). I put them on and ran them only to find them slightly and annoyingly warped; I didn't have time to get to them for a couple of hundred miles at which point I pulled them, had them turned and the problem went away. Sounds like it would be worth checking yours....