Fuel Economy gives you a ball park mpg on your vehicle.
Ford Ranger 2.5 4cyl. 5-spd is 18-cit.& 23Hwy
6 cyl. 5-spd 16 mpg cit. & 21 mpg hwy.
ethenol content can make big difference also.
Also clogged cat. or muffler.pcv valve
I did not think of the PCV but I will assume that you can easily test that the same way as on my car. With the truck running take the oil fill cap off then place you hand over the hole if there is suction you will need to replace the PCV.
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