Repair

Fuel guage is probably the sending unit which is in the gas tank with the fuel pump. The low trac could be a wheel speed sensor or possibly the speed sensor on the output of the transmission. Does the speedometer work right? Normally these would show up with a diagnostic tool.

Low trac means you have low traction (eg. slippery roads in winter). As the above person mentioned, it may be the wheel speed sensor.

As for fuel guage, I had the sending unit and pump replaced in my 2004 Impala. The guage still tends to stick at the halfway mark despite the tank being full or empty. It gets better in summer and worse in winter. Go figure :)