Power Steering Pump

I Also Have A 2000 Silverodo 1500 Ext.cab With 40000 Miles. I Replaced The Power Steering Pump Twice Within 800 Miles. It Seems That When You Turn A Hard Right It Snaps The Shaft In The Pump. We Are Still Trying To Figure Out Why This Happens. Of Course The Dealer Doesn't Want To Know Anything About The Problem. Does Anyone Have Any Suggestions. I Will Try Anything.

I'm thinking your pump is going to hydraulic lock, and the engine via the drive belt is snapping the shaft.

At this point one might lean towards the hydraulic proportioning valve inside the Rack&Pinion?
I always thought that the power stearing pump it-self had built in over pressure protection, but sense you tried two differant pumps this might not be the case.

When you figure this one out let us all know.

-Mike

I'm not sure but i think i just seen some thing on this about a recall, check it out. Could save you some work and a little cash.