fuel gauge acting funny

[funkingonutz]

ever since i replaced the fuel pump and sending unit on my '95 supercab my fuel gauge has been acting a little slow. ill go fill up and it will just stick there for like a whole day of driving and doing errands....(then the scary part) and it will just drop like a whole quarter tank all of a sudden...then it will change its mind and go up to where it was before.
my gas light turned on once and i know for a fact i had at least a quarter tank...so then i shut the truck off and turned it back on but did'nt start it, and i watched the fuel sudenly "appear" in my tank..
WTF this is really annoying....before i did the fuel pump and sending unit i did'nt have this problem.
someone help......could it be the gauge itself thats messed up???
thanks

 

[Wicked_Sludge]

if it wasnt acting like this before you replaced the sender then the guage is probably not the cause (though it is still a possibility).

are you sure you get the sender for the right wheelbase/fuel tank size? did you get the connecter on the top of the pump/sender plugged in firmly?

 

[funkingonutz]

yes its the Ranger Supercab fuel pump, yes its plugged in firmly and thier is electric grease all over the connectors.