picked up a new tc rs 7.0 about two months ago and got all the bells and whistles on it. one of witch was the trd lowering springs. after about a week i noticed some knocking in the rear when going over small bumps nothing crazy just really annoying. the bad part is when i hit those slightly bigger bumps the rear end expells a loud clunk. i was wondering if this is normal or should i bring it to the dealer and have this checked out? does anyone have any idea what it might be so i can possibly point them in the right direction?
p.s. bought the car with them on. did not install myself or anything.

 

rear strut rubber bushing if not installed can make a clunk, i know the fronts on the xb can clunk if the top hat is not positioned on the strut properly, all you need to do is dissassemble te strt and line up the hat properly

 

but i run and xb not familiar with the tc but id look into the rear strut bushing first

 

Can't believe more people haven't posted. Lots of people in this section have had this issue. The TRD springs seem to be very picky about the way they are installed. Look at Zeroeyeque's build thread. This was one of the first mods he did, by the dealer to get warranty, and he had to take it back like 3 times because they did not pay attention to the directions. This is probably what happened when the springs were installed; be it at the dealer or the port, (you didn't specify) and as such will be under warranty. HOWEVER, if you take it in and say "there is a noise, fix it," they will do everything they can to do as little as possible. I advise doing some research on the forum, and bookmarking several pages where people had the same issue, then taking your laptop with you to the dealer and showing the service writer.