powersteering pump

[dammitmitchell]

hey yall.
Do the PS pumps in our trucks contain a shear section or woodruff key in them?

reason i ask is because i was driving and upon untering the HWY i heard a loud bang under the hood, (been tuning alot recently but thought it was an intake pop. but due too many suporting reasons it definatley was NOT an intake pop). But here's the weird part. went to pull off that the dang power steering is unpredictably intermittent.
It comes and goes.. belts are tight and i get the occasional squeal. but man.. i just cant find a breakdown of the PS pump. this is the third in two years.. i need a new manufacture..


grrrr..
(well im assuming it's time to warranty this one... but crap man.. )