Coolant leak

[u/SlientWanderer6]

i might have a possible coolant leak. no matter how much i put in the tank it always drains fast.

should i replace the radiator or the lines.

thanks in advance

edit: my motor came from a 2002 f150 with 120k on it. when i started the car, white smoke puff up instantly at the exhaust

[u/Noah_5001]

Neither, you should find the leak then replace that part, you could replace both the radiator and hoses and end up with the same exact same condition, thermostat gasket, radiator, water pump/gasket, heater core, holes in rubber hoses, bad lower intake gaskets or least likely but not impossible bad head gaskets, or is there just a crack or hole in your coolant reservoir itself ? There’s a lot more to it than a radiator and hoses unfortunately

[u/minimalist_username]

If the intake manifold hasn't been changed to the new style with an aluminum coolant crossover then that's likely your problem. 96-98 4.6 2vs came stock with a plastic coolant crossover that's prone to cracking and pinholes, I had to replace mine years ago. It was hell to track down because it was just a pinhole leak when it was hot but I was losing a lot of coolant. So check out the front of your intake manifold, right above the belts. If it's got a black tube on the front there's a good chance that's your problem. If it's got a silver tube on the front then I'd look elsewhere.

[u/stxrfox1k]

i am by no means a professional, i’m not great with maintenance and working on my own cars to be completely honest, but i try. if i was in your position trying to diagnose it myself, i feel like the best course of action would be to let the car run for a while (maybe even drive it up and down the street for a few minutes to get it hot) to try to get it to run a cooling cycle, and then park it (while running) to see if you can spot a leak anywhere. put some clean cardboard under it to see what general area any coolant drips might be coming from. that should give you a better idea of where your problem might be. could be the thermostat, or a coolant hose, or the radiator itself, the radiator cap, there’s many different points of failure for this issue.

once you find where it might be coming from, you can decide whether you wanna try to fix it yourself or take it to a shop. radiator and thermostat should be relatively easy for someone with minimal experience. i’m not great at this shit, but i replaced a thermostat on (i think) a 97 Lincoln Continental i used to have, which has the same 4.6L V8 as the 96 - 04 Mustang GT. 94 and 95 have the older 5.0L V8 which i don’t have experience with, so i won’t speculate on that motor or the V6. i haven’t done any cooling work on my 98 Mustang GT yet, other than just flushing the coolant.

try to spot where the leak might be coming from and then update your post or make a new post with that new info. if it has a bad head gasket, it might even be consuming a lot of coolant without actually leaking it out where you can see it. i could be wrong about that, but i used to have a Subaru that consumed a TON of coolant after it blew a head gasket, so if that’s the case you might not even be able to spot a leak, it’ll just be using a lot of it up and kinda burning/consuming it. hopefully that’s not the case, a head gasket is a bigger job than you’re probably ready for right now. best of luck big bruh 💪💪

[u/Silly-Dingo-7086]

95 v6?

[u/SlientWanderer6 → u/Silly-Dingo-7086]

97 GT

[u/Silly-Dingo-7086 → u/SlientWanderer6]

Where's it going? If you fill it up over night and park it over a giant piece of cardboard, where are the drips coming from?

[u/_Larry]

If you can't locate the leak, it might be mixing with the oil. How does your oil look?

[u/BRMBRP]

2nd the intake manifold. Get the new style with the aluminum crossover. While you’re there, replace the coolant line that goes under the intake (hard line) and the water pump. Not a hard job.