doesn't sound like it to me
if you need a new wash arm support you can get it from hobart, or there is a complete wash pump housing on e bay right now for 50 bucks.
the post that the hydrosweep sits on and spins around should be firm and not loose at all.
i bought a kds-19 a few years ago, it was my first kitchenaid when i began my collection and the first thing to go was the wash arm support. i hear it's a common problem although out of all my kitchenaids i have now i have had to only replace two. 2 out of 18 aint bad!
good luck with it, ity's an easy fix if that is the problem.