Mine has always read 3/4 when the tank is full. I replaced the entire wiring harness and sending unit a few months ago, and she still reads 3/4. I have no doubt that my problem is the gauge itself, and most likely everybody else's who get a false reading at the gauge. I may try ordering a new gauge just to prove my point.

 

JMD - I tested that last night. It turned out it was reading incorrectly, slightly. I tightened it on the stud this time correctly (last time I did it at the gas station by hand). So that helped, a little. Thanks Soaring, I will give that a shot.

 

Mine reads 3/4 when I fill it up. When it reads 1/4, I head to the WaWa and fill it back up.

I am living with it for right now but it's on the list of things to fix after I get the transmission looked at.

 

I don't doubt you a bit Glen. With your knowledge of these cars you don't need to prove anything to me...

My reading of the original post led me to believe that the gage may have worked properly prior to My Savior replacing the tank, The float, sender,andgauge issues had already been covered so I wanted to add the possibility that the connection might have been poor.... I didn't want to see the OP spend a bunch of money over a bad connection!!! I knew that this was an outside chance, but still a possibility...

Take care Glen!

 

I'm lucky to get a reading of more than half a tank when in reality the tank is more than full. Used to only be a quarter of a tank low on the reading but it's just gotten lower as of recently. Makes me think the main problem I have is a bad float. I know it wouldn't hurt to replace the tank though, the car did sit outside our house for years with gas in the tank, but it did immediately start up when we put a new battery in after all those years.

Makes me wonder if the people who built these mustangs also built gremlins

 

My problem turned out to be a bad conncection at the tankalso. I pulled the wire off to check the sending unit & it all checked out OK so I put the wire back on the stud. Checked the gauge & it was reading correctly now so I guess it was a loose/bad connection. I was happy.