How to Replace the Radiator Hose on a 2018 Hyundai Sonata (Upper or Lower)
Step-by-step instructions with required tools/parts, coolant safety tips, and refill/bleed guidance
How to Replace the Radiator Hose on a 2018 Hyundai Sonata (Upper or Lower)
Step-by-step instructions with required tools/parts, coolant safety tips, and refill/bleed guidance
🔧 Sonata - Radiator Hose Replacement
Your Sonata has multiple coolant circuits (engine radiator, and hybrid/EV cooling). The replacement steps and parts are different depending on which hose you mean, so I need one quick confirmation before I give you the exact, correct procedure.
Difficulty Level: Intermediate | Estimated Time: 1.0-2.5 hours
⚠️ Safety & Precautions
- ⚠️ Never open the coolant reservoir/cap hot; severe burns can occur.
- ⚠️ Your Sonata is a Plug-In Hybrid—avoid orange high-voltage cables and hybrid components while working.
- ⚠️ Use jack stands if lifting; never rely on a jack alone.
- ⚠️ Coolant is toxic—keep away from kids/pets and clean spills immediately.
🔧 Required Tools
You'll need the following tools for this repair:
- Safety glasses
- Nitrile gloves
- Floor jack (rated 3-ton minimum)
- Jack stands (rated 3-ton minimum)
- Wheel chocks
- Trim clip removal tool
- Flat-blade screwdriver
- Hose clamp pliers (specialty)
- Pick tool
- Catch pan (at least 2-gallon)
- Funnel
- Shop towels
- Work light
🔩 Required Parts
HowToo sells all the parts you need for this repair:
- Radiator hose (correct position) - Qty: 1
- Hose clamps (OEM-style) - Qty: 2
- Hyundai-approved coolant (pre-mixed, correct type for circuit) - Qty: as needed
đź“‹ Before You Begin
- Park on level ground, set the parking brake, and let the car cool fully (ideally overnight).
- Make sure the hybrid system is OFF and the car is not charging.
- Place a catch pan under the front of the car before loosening any hose.
🔨 Step-by-Step Instructions
Follow these steps in order:
Step 1: Confirm which “radiator hose” you mean
- Please answer these two questions so I give you the exact hose routing, coolant type, and bleed method for your Sonata:
- 1) Is it the upper radiator hose (top of radiator to engine) or the lower radiator hose (bottom of radiator to engine)?
- 2) Is the hose on the engine radiator (thicker rubber hose near the radiator) or the hybrid/EV cooling circuit (often smaller hoses near inverter/electric components)?
Step 2: Next steps after you confirm
- Once you confirm, I’ll provide the exact removal order (including any undertray clips), where to drain, and the correct bleed procedure for that circuit.
- Tip: A photo helps confirm the hose.
âś… After Repair
- After I provide the correct bleed steps for your hose/circuit, you’ll refill to the correct level and verify stable temperature and proper cabin heat.
- Recheck the coolant level after the first drive and again the next morning when cold.
- Inspect for leaks at both clamps with the engine warm.
đź’° DIY vs Shop Cost
Shop Cost: $250-$550 (parts + labor)
DIY Cost: $40-$150 (parts only)
You Save: $210-$400 by doing it yourself!
Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 1.0-2.5 hours.
🎯 Ready to get started?
HowToo makes it easy: same-day/2-day shipping on every part, plus all the tools and specialty tools you need! Check out the parts and tools sections below to add everything to your cart.
