I have a 1998 Ranger with 2.5L and 5 speed it has 283,000miles on it and I gave it to my brother to use because the transmission went out in his car he used it for the last 50k miles or so, I just got it back from him and I used to get 27 mpg fwy and 24 city now I'm lucky if I get 20mpg. Is there something specific that could cause this? I have no CEL and it seems to run good.

 

Crappy gas.
Gotta love that ethanol blend. Guaranteed to lose mileage.

 

If he had it for the last 50k miles, you should probably change the fuel filter and air filter.

 

This ^. Also spark plugs/wires and possibly an o2 sensor.

 

and it has 283K on it...its not gonna get the same mileage it used to

 

Man I don't think I have ever gotten 27 hwy and I've had my truck since 64k. Now it has 158k and right now I get 24 hwy and about 19-20 city

 

I get 27 highway and about 22 city. Thats with an automatic and 170k miles. I did a tune up at 150k with new spark plugs (sp432 motorcraft), BWD wires, BWD PCV, Wix air filter, and Wix fuel filter.

Then only thing that I have on the truck is a Poweraid Throttle body spacer (Got it for 20 bucks so I figured what the hell). I'm sure it doesn't do a darn thing.