Looks like they do exist, but you aren't going to save much money (unless you go with the 2wd). These numbers are from
Fuel Economy and are for a 1999 Cherokee.
Type, engine, Transmission, MPG city, MPG highway, Anual fuel cost
Jeep Cherokee 2WD
4 cyl, 2.5 L, Automatic 3-spd, Regular 16 20 $2628
Jeep Cherokee 2WD
4 cyl, 2.5 L, Manual 5-spd, Regular 18 23 $2235
Jeep Cherokee 2WD
6 cyl, 4 L, Automatic 4-spd, Regular 14 20 $2794
Jeep Cherokee 2WD
6 cyl, 4 L, Manual 5-spd, Regular 16 22 $2485
Jeep Grand Cherokee 2WD
6 cyl, 4 L, Automatic 4-spd, Regular 14 19 $2794
Jeep Cherokee 4WD
4 cyl, 2.5 L, Manual 5-spd, Regular 16 18 $2628
Jeep Cherokee 4WD
6 cyl, 4 L, Automatic 4-spd, Regular 14 19 $2794
Jeep Cherokee 4WD
6 cyl, 4 L, Manual 5-spd, Regular 15 20 $2628