just noticed i hear a subdued popping like noise when i turn a hard left, but it is not limited to that only. it kind of sounds like running over air filled packaging material only not as loud. this is a btand new 10' w/ 600miles
If you do a bit of searching on these Lambda forums you will see other threads describing similar symptoms to yours. The key to getting dealer service (e.g. rack replacement) is the ease that your Traverse can reproduce this sound with a service rep/mechanic present.