Use the EPA numbers for that era to get a good comparison. They may not be perfect but IMHO are pretty decent for just comparing.

The Montero SB better than a F150. It weighs at least a 1000 LBS less and typically has a smaller engine.

My experience is that a typical F150 on short trips around town should get around 11-13.

web page

Kevin

87 Turbo Intercooled Raider, roller cam, torsen rear diff, LSD front diff, lockup auto with modified converter, V6 brakes, low transfer case gears...