Just to follow up on this. It seems the Cruze has different spring height when it comes to different model:Hi Guys, I just found on the cruze forum that the spring length change happened 12/11(I don't know if this is november of 12 or Dec of 11).
See here: KYB struts/shocks
Did you have the TSB performed on your car for the front shocks at any point? If not, you'll need new springs as well if getting Bilsteins, as GM redesigned this after the 12/11 production month, which resulted in a lower spring perch and longer spring. You'll want to pick up front springs for a later VIN 2012+ or a 2013+ Eco as your front springs are too short. If you did have them replaced due to clunking noise early on, you'll have the new design.
So I'm guessing this post is not accurate if you buy anything later. No wonder on all the major sites the struts listed for cruze and volt are the same.
For the most mild lowering, you can simply pull springs off of another Cruze with the Eco or RS package. Be sure the transmission matches the vehicle you are pulling the springs off. The Eco/RS springs are 10mm lower than other Cruzes are.
You can find the original text in the cruzetalk. Improving the 2011-2016 Cruze Handling & Suspension