Bill Barnes
Member
I have a 2005 Yukon XL with ZW7 Premium Smooth Ride, which I bought new. I changed the factory shocks at 90K, and did not have Nivomats on the rear. GM gave me the exact same shocks,, based on the VIN, and confirmed the ZW7 code. Early this year, in prepation for a trip from Virginia to Chicago, then taking Historic Route 66 to Santa Monica, I decided to upgrade to Bilstein shocks at 196K. Rock Auto, Bilstein, and Amazon all showed the same parts, specifying that I also had to purchase the new rear springs because of the ZW7 code. Everything went well, and I wish I had done this at 90K instead of the AC Delcos!
