This morning on the way to work, I stopped at a stop sign down the street from my home. Upon putting my foot to the gas lightly to accelerate , I heard a very distinct POP. I thought I blew out a tire, but the tires were all intact. Upon accelerating, there is a tiny bit of vibration that quickly goes away, but when the car accelerates or is stopping for braking, there is a very distinct clunk sound coming from the back. It also sounds like something is not quite attached. I took it to my mechanic on lunch, and he drove it around, put it on the alignment rack, and could not figure out what the cause of the noise is, He says everything is relatively tight and the only thing that is borderline are the lower control arms. He said they look to be on the way out but could not 100% confirm that is the cause of the noise. I do realize it is an older car but I want at least one more year out of it. What gets me is that pop sound I heard this morning.

I have a 2005 Chevy Trailblazer, with 100,000 miles. My tie rods are only a few months old, the U joint was replaced last summer and for my most recent inspection I got my sway bars replaced along with the front wheel bearing.

Wondering what the heck it could be...