* With the 4.3L V6: Expect around 15-17 mpg combined (city and highway driving). City mileage would be lower, and highway mileage higher.
* With the 2.2L 4-cylinder: You might see slightly better fuel economy, perhaps in the 18-20 mpg combined range, but this is less common in the ZR2 trim.
These are estimates, and your actual mileage will vary based on driving habits, terrain, vehicle condition, and other factors. Remember that these are older figures and may not reflect the real world performance of a specific vehicle, particularly one that has aged.