Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
Hello I will help you with your question,
You should be able to look for the code on the RPO tag in the glove compartment, if it is not there you do not have that option.
If the shocks are not leaking and pass the bounce test I would not be replacing them. Any aftermarket shocks will have a very different ride from the OEMs and it may not be pleasant.
Are the shocks dark yellow and say Bilstein on them?
It will have the three digit Z83 code you asked about if it has that option. That is what the RPO tag is for to identify the regular production options that were put on the vehicle.