Bilstine struts/shocks questions

Shift518 Automotive
1

I have a set of hd yellows and was wondering if they are rebuild able? I only have about 20k at most on the set up but I’m getting a clunk from the rear and I’ve diaged it as the shocks

2

Bilstein

http://www.bilsteinus.com/products/search-service/service.html

3

Awesome thanks!