I bought a 2001 suburban LT with 120k on it and the widow sticker was in the glove box. It listed "premium ride suspension". Would that mean that it has the z71 Bilstien shocks? I am wanting to replace them because it does feel very jiggly (hi-tech term) when hitting rough road areas. I am wanting to put in something better than oem. Are Bilstien shocks the best bet regardless? Any other suspension parts that commonly wear out for that amount of mileage that I should be looking at?