99 Ranger Mileage

[Deborah Yohe]

We have a 99 ranger (4.0L) 4WD. The gas mileage is terrible - 10 miles to the gallon. Mechanically, it seems to be in great shape. What is the average mpg for a 99 and are there any suggestions on what could be causing the low mpg?

 

[shadyluke]

How are you calculating fuel economy? Could be an error there. Proper way would be to reset your trip when you fill up then at the next fillup divide the miles traveled by number of gallons needed to fill back up. Sounds dumb but sometimes it gets screwed up. 10mpg is really low. My 2000 with the BL, 33s, and the light bar on the roof still sees 14-15mpg on the highway. I would suggest a tune up. Fuel filter, plugs, wires, and even clean the MAF.

 

[RangerX]

Does it have stock size tires? If not, did you regear the speedometer cable? If not, your odometer is off.

Welcome to the forum.

 

[yohe]

Gas Mileage

Hey guys. A little back info on the ranger she's talking about, since it's my brothers. It has the stock tires and just recently had a very expensive tune up. I have ruled out any electrical problems due to the fact there are no codes and it's running great. The thoughts crossed my mind about incorrectly gapped spark plugs, clogged fuel injectors, etc, but all of this would still cause a little bit of a rough run don't you think? Tires were recently balanced and are kept at about 35-38psi and rotated regularly. The oil is changed every 3000 miles and the air filter is checked regularly to rule that out.

Does anyone have any other possibilities that might not set off a code?

Thanks.

 

[Desert Explorer]

Brakes. Check to see if the wheels rotate freely, sometimes brakes will contact when the pedal is not depressed.

 

[yohe]

Yep, the wheels move freely. Nothing seems to be catching anywhere that I'm aware of. Lining, calipers etc are all in great shape. Thanks though.

 

[RangerX]

Temp guage reading normal? A stuck-open thermostat could hurt mileage, but I don't if by that much.

 

[yohe]

Good idea, I'll have to check on that one. I'm not sure. Thanks.