If your vehicle is showing green, pink, or orange coolant puddle under the front of the car, here are the most likely causes and the parts you'll need to fix each one.
Rubber radiator hoses degrade from heat and pressure over time, leading to cracks or pinhole leaks. A loose hose clamp from recent maintenance is also a highly frequent culprit.
The water pump circulates coolant through the engine. When its internal bearing seal begins to fail, coolant intentionally leaks out of a small 'weep hole' to warn you before a catastrophic failure occurs.
Modern radiators typically use plastic end tanks crimped to an aluminum core. Constant heat cycling makes the plastic brittle over time, eventually causing hairline cracks and leaks.
Plastic thermostat housings can warp or crack from engine heat. If the thermostat was recently replaced, a pinched gasket or improperly torqued bolts will cause an immediate leak.
The plastic overflow tank expands and contracts with hot coolant. As the vehicle ages, the plastic becomes brittle and cracks, allowing coolant to slowly drip down.
The drain valve at the bottom of the radiator can leak if its internal O-ring degrades. It is also very common for it to leak if it wasn't fully tightened after a recent coolant flush.
A severe engine failure where the gasket sealing the engine block and cylinder head fails outward, allowing coolant to leak down the outside of the engine block.