First lets look at similar trucks released by Ford, Chevy and Toyota.
2018 F-150 2.7 4x4 10spd auto EPA: 19/24/21
2018 Colorado 2.8 4x4 EPA: 20/28/23
2018 Colorado 3.6 4x4 EPA: 17/24/19
2018 Tacoma 3.5 4x4 EPA: 18/22/20
Now assuming that the Ranger is several hundred pounds lighter than the F150 and utilizes a small engine, we can guesstimate the rangers EPA to be around 21/26/23. This would bring it right up to bar with its GM competitors. Not to mention it should be a good deal quicker than diesel offerings.