I wouldn't say you need a stall. But you'll definitely want one when your truck is a total dog under 2000rpm. IMO, a stall converter comes before or during a cam swap.

 

I agree, with the cam you listed in a 5.3, I'd say at least a 3k stall is in order...probably better off with a 3600 stall considering all of the duration that cam has. If you want to optimize the powerband that this cam will provide, a stall is a must