false reading - fuel gauge

[HondaFan81]

For the past week I feel my fuel gauge is giving false readings and for some reason the needle will not go to the Full mark when I fill up at a gas station. Like today I waited until the needle was like at a 1/4 tank or lower and then I filled up to 10.6 gallons and the needle only went to the 3/4 mark after I had filled it. Weird. Could this be related to a alternator going bad?

We have a Chevy 2500 truck that's a company truck and it recently had alternator probs (left me stranded on road couple days ago 67 miles from work!) ...anyways, the guy that drove before me was saying it gave false readings on the fuel gauge a few days before the alternator crapped out....so that got me wondering.

What you all think? Anyone had this prob? If so, what was the cause?

[92accordf20a]

do u have any gauges installed on ur instrument cluster, also have u been using shell gas??

[dj justice]

whats wrong with shell gas?

[92accordf20a]

well a couple a weeks ago I saw something in the news about shell gas containing to much sulfur. the results of this is, It would throw your fuel gauge of by making it read like u have gas when u really don't..

[Slateboy]

I go by my gas light. It works.

[HondaFan81]

no aftermarket gauges installed of any kind, everything is completely stock...also I haven't put Shell gas in VERY long time just cuz I don't run into it much wherever I happen to be

[92accordf20a]

ok, it could be your fuel sending unit located in the tank, or it can be ur actual gauge cluster.. In my opinion i would check the fuel sender in the tank first cause there's a good chance that it might be the cause of your problem

[HondaFan81]

ugh, that would suck....