The EPA has published the fuel economy numbers for the 2018 Jeep Wrangler Unlimited 4-Door (JLU) V6 model and they are a couple of MPG better than the outgoing JKU V6 model. Here are the MPG figures:
3.6L V6 Pentastar with 8-Speed Automatic Transmission (JLU):
20 MPG combined
17 MPG city
23 MPG highway
3.6L V6 Pentastar with 6-Speed Manual Transmission (JLU):
19 MPG combined
17 MPG city
23 MPG highway