Just had Blue aligned, and now almost every time I step on the brakes, (problem is intermittent) there is a thud in the rear passenger area. I already bled the brakes and took off the drum for inspection. Nothing looked out of place. No obviously loose bolts or anything. Anybody have this happen or have an idea of what’s going on?

Maybe the bearing slid forward on the axle when ya put on the drum, my 93 Loyale 4x4 had some weird issue like that... I had to push the bearing back and hold the axle forward and slap the drum back on before is came out again...

Check the bolts securing the trailing arm to the outer arm.

 

Those 3 are where the alignment adjustment happens, so that should be the on;y bolts the alignment shop would have touched.  

 

Unless they tried to move the entire rear subframe to set thrust angle......then the main crossmember bolts would be what to check.