Recently bought a 02 Ford Ranger edge (3.0). When I bought it, it had a half tank of gas. I got it down to about a quarter then I filled it up. I started the truck and it only went up to 3/4 tank, so I drove to work when I got off I turned the truck on and the needle went past full then back to 3/4 after driving a little. I started it this morning and it did the same thing but while driving like once or twice it went up past full then back to 3/4. Any idea what my cause that. Worth noting that the guage lights don't work behind the gas guage and engine temp guage which are both on the left side. I also have put 90 miles on that gas tank fill up and it still stays at 3/4.

 

Welcome to the forum

There are 6 light bulbs in the cluster that light up the gauges with lights on and a dimmer wheel to adjust the brightness of those 6 bulbs
Not uncommon for a few to burn out over the years, there are 2 separate circuits with 3 bulbs each
If you pull out the cluster change all 6 bulbs
There are LED bulbs now that fit but they need to be put in the correct way, LEDs have a specific + and - side which regular 12v bulbs don't have

Up to thru 2003 Rangers have an Anti-Slosh Module on the back of the cluster, these can fail, but usually they show Empty or Full all the time, but there can be more than one failure mode
If you go here: https://www.ebay.ca/itm/314589882273

4th picture down shows the back of the cluster, you can see the anti-slosh module at the upper right, it's a slide in module so can be swapped out

 

Thank you very much, nice to know they have leds now. I have a Ranger scrapyard nearby so might head over there and grab a couple of the slosh modules and test them out!

 

1996 thru 2003 Ranger/Mazda B-series clusters are interchangeable, plug and play, exactly the same wiring
You can even upgrade to one with a Tachometer if you want one, all are also wired for a tach whether cluster has one or not

 

I recently changed a Fuel Pump Assemmbly that had the Brass Float on it. The brass float was half full of fuel that thru off the gas gauge reading.

 

Good to know, might be similar problem here. After driving it for a while the guage starts to work like half way in between 1/2 tank and 3/4. Makes me think it’s probably something with the float!