Trailarm Bushings
 

Just had my 2007 mazda3 in for safety inspec. Would not pass cause the bushings are gone in the rear trailarms, There is 30,000 miles on it no noise from the rear etc. just a $450 repair bill ? The dealer did not have the parts in stock so job not done yet!! Just cannot believe they are gone so soon? any thoughs

If the bushings are truly gone you'd get some vibration when driving and have horrible tire wear as well.
If parts (wheels etc...) aren't physically loose on the vehicle it will pass safety inspection.
So i'd vote to have a local garage look at it - or look yourself.

Ah, that should also be under warranty though, you're well within 36mo 36k miles, and it's not a wear item (tires, brakes, shocks). They should never need replacement or maintenance. So tell them since they said they are bad, that they need to fix it under warranty... end of story.