Well, it wasn't the belt. That bad boy was nice and tight. Does it need to be bled? If so how do you do that?

 

How much lift do you have on the truck. If you are using the stock drag link from the gearbox to axle that might be a problem. It'll be pushing down as well as pushin sideways. My old k5 had 38s on 1/2 ton stuff and steered fine

 

mine seemed tight to. i loosened the pump and took a pry bar and pryed away while tightening down the pump. to bleed you turn left to right. lock to lock. you could have a line with a hole in it getting air in too.