I put in a new gas tank and fuel sender but when my tank is full the gauge only reads 1/2 full is there anything i can do to fix this problem?? just wondering if anybody else has run into this problem

i had a similar prolem with my roadrunner....the gauge was for a different ohm range than the sending unit. is it a stock sending unit?
mine was a fuel cell, had to order a different gauge. hope this helps

(1) run a long jumper wire from the sending unit flat circular metal surface all the way directly to the battery negative post to make sure it's grounded well (2) pull the blue sending unit wire and ohm the sending unit stud to the same flat metal on the sending unit face & post what you get. probably need to get the tank close to empty and pull the sender & eyeball the rheostat and ohm it thru it's travel and at the top and bottom of it's travel.

After you verify the ohm ranges for the new sender and your old gauge, I would pull the sending unit completely out, jump a ground wire to it, and hook up the sensing wire.

Then turn the key on and swing the arm through its range and make sure the gauge shows the same thing. If you can get full and empty on your gauge you'll need to tweak the arm to make it read right when its in the tank. This may take some trial and error to get right.

(Don't leave the key on for longer than a minute though; it may burn out the points/coil?)