* Engine size: While it's a 6-cylinder, the exact displacement (e.g., 4.0L) matters. The 4.0L was the most common.
* Transmission: Automatic or manual transmission impacts fuel economy. Manual tends to be slightly better.
* Driving conditions: City driving yields significantly lower MPG than highway driving. Terrain (off-roading drastically reduces mileage), speed, and even weather affect gas mileage.
* Vehicle condition: Proper maintenance (tune-ups, tire pressure) is crucial for optimal fuel economy.
Generally speaking: You can expect to see fuel economy in the range of 13-17 MPG combined (city and highway driving) for a 1997 Jeep Wrangler with a 4.0L 6-cylinder engine. Highway driving might push it closer to the higher end of that range, while city driving will likely be closer to the lower end or even lower.
It's important to note that this is just an estimate. Real-world mileage may vary.