2000GMC Yukon off-road suspension??

I was wondering how i could tell if i had the off road Z-71 suspension or not on a 2000 Yukon. It has skit plates, no running boards, and the upgraded chrome rims, and all of the newer yukons offer an off road suspension that come standerd with skid plates and premium rims. On the Z-71 tahoe you can easily tell because its a seperate trim level unlike the Yukon. (Z-71 Tahoe) Any help would be appreciated.