i lowerd my tc 2 '' with the gold line springs and left my stock rear shocks and my stock front struts,its been about 15k miles but i belive that my rear struts have gone out i want to replace all for struts but i dont know with what help?

Why do you think your rear struts have blown?

cause when i go over a bump i can hear a clunk and hits hard this was no there before besides i belive its time for new ones its been 15k on them with the goldline 2'' lowering springs

My rear is lowered 2" (hotchkis) and I'm going on probably 35k+ on OEM struts.

Typically if your struts are blown you'll get a LOT of bouncing. If its a clunk, I'd just get it checked out first and make sure something else isn't wrong.

That said, if you're looking for replacement struts... the TRD ones are just fine for just about any application.

ill pay more attention to them thanks

What are the best performing struts you can get? and how much would you be looking at to spend on a set of 4?

ya what ack said if you have blown them there will be a lot of bouncing and there will prolly be a lot of old grease on the outsides of the struts that have been coated with dust and dirt the sound you hear is prolly your bumpstops not a blown shock you should go over bumps slower unless you dont care but thats just me you can get TRD cuz they are pretty good they should last a lot longer than 15k

(whew)

But isn't the TRD shocks designed to go with the TRD springs? Goldline's and other springs go way lower than the TRD springs.
You would be shortening the travel of the strut with a lower spring depth than the TRD springs right?
Or does it even matter?

there are no struts that extend the travel for the tC afaik. whether it's TRD, monroe, koni, tokico, if you lower the car, you're going to be sitting closer to the bumpstop.

also, just in case someone asks, struts and shocks cannot lower the ride*, because the car sits on the springs. All shocks/struts do is absorb (dampen) the recoil of the springs.

* unless they are so short that they actually compress the spring, but that's plain stupidity.