Finding a puddle of green or pink coolant under your 2020 Pathfinder is concerning. When the radiator is leaking, you're losing the fluid that keeps your engine from overheating. This needs attention before that small puddle becomes a big problem.
Signs of a Radiator Leak
- Coolant puddles under the front of the vehicle
- Sweet smell when engine is warm
- Visible coolant stains on the radiator
- Coolant level dropping without overheating
- Steam from under the hood (if severe)
- Temperature gauge rising higher than normal
Common Radiator Leak Locations
- Plastic tank seams: Where plastic end tanks meet the aluminum core
- Hose connections: Upper and lower hose fittings
- Transmission cooler fittings: Lines connecting to the radiator
- Stone damage: Road debris puncturing fins or tubes
- Corrosion: Internal deterioration creating pinhole leaks
Plastic Tank Seam Failure
Modern radiators use plastic end tanks crimped onto aluminum cores. The seam where plastic meets aluminum is a common failure point. Heat cycling causes the plastic to become brittle, and the crimped joint develops leaks. This is often not repairable—the radiator needs replacement.
Quick Assessment
- With engine cold, open radiator cap and check level
- Start engine and observe the radiator for leaks
- Check upper and lower hoses and connections
- Look at the transmission cooler lines (if equipped)
- Inspect for wet spots on the radiator core itself
Repair vs. Replace
Can sometimes be repaired:
- Loose hose clamps
- Damaged hoses
- Minor fitting leaks
Usually needs replacement:
- Tank seam leaks
- Core tube damage
- Multiple pinhole leaks
Repair Costs
- Radiator hose replacement: $100-$250
- Hose clamp/fitting repair: $50-$150
- Radiator replacement (aftermarket): $300-$600
- Radiator replacement (OEM): $500-$900
- Transmission cooler line repair: $150-$350