2005 Ranger 2.3L 5spd 2WD XL 374,000. miles.

I drive about 180 miles a day and on the last few tanks of fuel the fuel guage started dropping off of full alot slower than normal even though still needing to fill up every other day.
On the third tank the gauge dropped down to about one half, took 12.5 gallons to fill (16 gal tank), gauge returned to full then in 5 miles fell to Empty and fuel light came on. Next morning the fuel light was on gauge at empty for 15 miles then jumped back up to full. Still getting normal mpg and running well.

Any thought on what may be wrong?

Thanks all.

 

Try a 20 oz Chevron Techron Plus in the tank at the pump before filling, so to get good mixing & run most of the treated tank out before refilling, as Chevron says Techron can tidy up sulfated fuel level sending units that act out when we use fuel with high sulphur content. Let us know how it goes.
EDIT: If you have the small fuel tank, its 17 gallons.

 

Update
pawpaw thank you; you can always be counted on.
I filled up with Cheveron and added two cans of fuel cleaner, as soon as I filled up and started the truck the fuel guage goes to below empty and the fuel light comes on. Start my 180 mile drive in the morning on Empty and the fuel light on (tank is full) 30 miles into the drive guages jumps to Full and the fuel light goes out, guage still drops slow. 180 miles later and the guage has droped to 3/4 of a tank. On the second tank added one can Seafoam, filled up with Cheveron with the truck running guage at 3/4 and it fell to Empty and the fuel light came on. I see no wire issues but it is dark. Thinking of past electriconic issues I removed the (-) battery terminal after about 45 sec heard a click let it set for a while and when reconnected the fuel guage has gone to Full and the fuel light out. Will update after the next few trips.

Thanks FTE

Bob

 

Techron fuel treatment at the prescribed 1oz/gallon treat rate will raise the treat rate 10X above pump gas alone & have the PEA get after fuel sender corrosion, while also doing a tidy up job on the fuel injectors, intake valves, piston crowns & heads.
If we'll reguarly use PEA treated fuel, like Chevron, Texaco, Caltex & now Shell whos fuel ad pack contains a maintenance dose of PEA, its said that'll keep the sending units contacts clean.
If we like to mix our own treatment, add 1oz of Chevron Techron Concentrate Plus to 10 gallons of gas & achieve approximately the pump gas treat ratio. SO, a 20 oz Techron container would treat 200 gallons at the pump gas treat ratio & keep a lot of things tidy while we drive.


Seafoam doesn't contain any PEA, so won't likely have any affect on sending unit corrosion, if that's the problem. Let us know how it goes.

 

Second update

Fuel guage issues returned. I have treated twice with Techron. Guage is slow to drop, indicating about 1/3 of the actual fuel usage. When you fill the tank it goes to F (full) and within about 5 miles drops to E (empty and the fuel light comes on). Next morning start out on 180 mile drive, guage on Empty with fuel light on, in about 30 miles it jumps to Full and starts the slow drop. This has repeated daily for about three weeks. On a 2005 Ranger XL is there anything between the fuel sending unit and guage that could cause this problem? Or is the next step to pull the box and change the sending unit?

Thanks FTE for the help.

 

Ok good feedback. Bummer that sending unit corrosion isn't likely the problem, as that was the easy fix!!!!
The "slosh module" is known to act out & cause fuel gauge reading woes, so move it onto your suspect list for inspection/check out.
Scan for trouble code clues with your ELM scantool running FORScan or the like software to the viewing device of your choice & post up All code Numbers.