The first-generation Jeep Grand Cherokee used the ZJ code.
Introduced in 1992 as a 1993 model-year vehicle, the ZJ was developed as a larger, more upscale successor to the compact Cherokee XJ and the aging Wagoneer. Its public debut became famous when Chrysler executive Bob Lutz drove one through the glass entrance of Detroit’s Cobo Hall at the 1992 North American International Auto Show.
ZJ production ran from 1992 through 1998. Early versions included Base or SE, Laredo, and Limited trims, while later additions included the Orvis Edition and the high-performance 5.9 Limited. Export-built examples assembled in Austria were designated ZG, a detail that can cause confusion when identifying international vehicles.
The later Grand Cherokee generations used WJ, WK, and WK2 codes, while XJ identifies the Cherokee rather than the first Grand Cherokee. That makes ZJ the single canonical answer for the first-generation Grand Cherokee’s internal code.