Do you have a manual or auto? That makes a big difference. The gov doesn't have info for a 97 online, but here are the gas mileage stats for a 1998 Jeep Wrangler:
| Engine & Trans | City | Highway | Annual Cost |
| 4 cyl, 2.5 L, Manual | 16 city | 18 hwy | $3343 |
| 6 cyl, 4.0 L, Manual | 15 city | 19 hwy | $3553 |
| 4 cyl, 2.5 L, Automatic | 15 city | 17 hwy | $3553 |
| 6 cyl, 4.0 L, Automatic | 13 city | 16 hwy | $4059 |
* Based on 45% highway driving, 55% city driving, 15000 annual miles and the price of fuel used by the vehicle.
I personally get 13.6 MPG
| Date | MPG |
| 10-Nov | 13.92927176 |
| 15-Nov | 15.72286013 |
| 20-Nov | 14.98198369 |
| 23-Nov | 15.28729573 |
| 30-Nov | 14.15187054 |
| 7-Dec | 13.7106826 |
| 17-Dec | 13.51619956 |
| 24-Dec | 13.94557823 |
| 30-Dec | 12.51727845 |
| 6-Jan | 14.49840713 |
| 11-Jan | 14.20560748 |
| 11-Jan | 18.11965812 |
| 11-Jan | 14.30948419 |
| 20-Jan | 16.30434783 |
| 25-Jan | 13.96172444 |
| 3-Feb | 13.65649606 |
| 12-Feb | 14.07641482 |
| 15-Feb | 14.00147384 |
| 22-Feb | 13.91663796 |
| 29-Feb | 13.07989691 |
| 3-Mar | 13.18565401 |
| 13-Mar | 15.91686398 |
| 23-Mar | 13.0560603 |
| 4-Apr | 14.2373747 |
| 13-Apr | 12.8758087 |
| 22-Apr | 13.11299926 |
| 27-Apr | 13.49838678 |
South's right about the speedo. If you put on larger tires, you'll travel farther with every revolution, and your speedo will report you going slower than you really are. You'll also show less miles on the odometer.