Car keeps overheating! I've tried everything!?

You have a leak or blockage (I assume the thermostat is working and was changed when the new rad was put in ... its standard proceedure) somewhere, if you are going through that much antifreeze. It could be a frost plug in the engine that has decayed. They are a small cheap part. Or it could be something as expensive as a crack in the block letting the coolant escape. I would check the frost plugs. There are at least 4 of them. Even minor pitting on them can cause a leak at warm temps. They are about $5.00 each to buy, or less. The car will have to be on a hoist to change them. If the thermostat was not changed, then change it first.

Check two things---

with the car running and the radiator cap off wait for the car to heat up and look into the cap to see if the water starts to circulate or not - if you can't see the water starting to move you have a bad water pump.

If this checks out I would go to a parts store and buy a tool, called a pressure tester, that you can hook on where the radiator cap goes and pump pressure into the cooling system. If it holds pressure you don't have a leak but if you see the pressure go down you have a leak somewhere in the radiator or hoses.

Maybe you got ripped off on the radiator? An electrical problem would have to do with leaking?

it could b a number of things a bad fan clutch radiator or house or water pump & more but first find out where its leaking fix that then go from there that might even b your only problem good luck

Coolant leak. if it leaks then fix the leak. If no leak but white smoke from exhaust. then cylinder head gasket, or cylinder head problem.

COULD BE THE TEMPATURE SENSOR AND THE TEMPERATURE SENDING UNIT,,,, OR THE THERMOSTAT,,,,

DO A SIMPLE TEST,,,NEXT TIME CAR OVERHEATS,,, RUN YOU HEATER ON HIGH, THIS SHOULD RUN YOU CAR TEMPATURE DOWN,,,,,,IF IT GOES NOT, IT MEANS YOU YOUR THERMOSTAT IS BAD,,,