🔧 Highlander - Radiator Hose Replacement

On your Highlander, radiator hoses carry coolant between the radiator and the engine. Replacing a leaking, swollen, or cracked hose prevents overheating and coolant loss.

Quick check: There are usually two main radiator hoses: upper (top of radiator to engine) and lower (bottom of radiator to engine/water inlet).

Difficulty Level: Intermediate | Estimated Time: 1.0-2.5 hours

---

⚠️ Safety & Precautions

• ⚠️ Never open the radiator cap on a hot engine; coolant can spray and burn you.
• ⚠️ Support the SUV with jack stands if you lift it—never rely on a jack alone.
• ⚠️ Keep coolant away from kids/pets; it’s toxic and sweet-smelling.
• 🔋 Battery disconnect is not required for this job.

---

🔧 Required Tools

You'll need the following tools for this repair:

• Safety glasses
• Nitrile gloves
• Drain pan (at least 2-gallon)
• Floor jack (rated 3-ton minimum)
• Jack stands (rated 3-ton minimum)
• Wheel chocks
• 10mm socket
• 12mm socket
• Ratchet
• Trim clip removal tool
• Slip-joint pliers
• Hose clamp pliers
• Pick tool
• Utility knife
• Funnel
• Shop towels
• Work light

---

🔩 Required Parts

HowToo sells all the parts you need for this repair:

• Upper radiator hose - Qty: 1
• Lower radiator hose - Qty: 1
• Radiator hose clamps - Qty: 2-4
• Toyota Super Long Life Coolant (pink) premixed - Qty: 1-2 gallons

---

📋 Before You Begin

• Park on level ground, set the parking brake, and let the engine cool completely (ideally 2+ hours).
• Set the HVAC to HOT and fan to low after refill to help bleed air later.
• Place a drain pan under the front of the SUV before opening any hose.

---

🔨 Step-by-Step Instructions

Follow these steps in order:

Step 1: Confirm which hose you’re replacing

• Open the hood and locate the hoses: upper hose at the top of the radiator, lower hose at the bottom.
• If you want, tell me: upper or lower (and if it’s leaking at the clamp or the hose is cracked). I can tailor the steps.

Step 2: Remove the lower splash shield (if needed)

• Chock the rear wheels using wheel chocks.
• Lift the front using a floor jack (rated 3-ton minimum) and support with jack stands (rated 3-ton minimum).
• Remove the front under cover fasteners using a 10mm socket and trim clip removal tool.
• More access helps, especially for the lower hose.

Step 3: Relieve pressure safely

• Place shop towels around the radiator cap area using shop towels.
• Slowly loosen the cap only when the engine is cold. No tool needed.

Step 4: Drain enough coolant so it doesn’t pour out

• Position the drain pan (at least 2-gallon) under the radiator.
• Open the radiator drain cock (petcock) carefully by hand; use work light to see it.
• Drain until the radiator level is below the hose you’re removing, then close the drain cock by hand.

Step 5A: Remove the upper radiator hose (upper hose path)

• Compress and slide the hose clamps back using hose clamp pliers.
• Twist the hose gently to break it loose, then pull it off by hand.
• If it’s stuck, carefully break the seal with a pick tool. (A pick tool is a small hooked tool used to separate stuck rubber from fittings.)
• If the hose is rock-hard and won’t come off, carefully slit it with a utility knife and peel it away.

Step 5B: Remove the lower radiator hose (lower hose path)

• Use hose clamp pliers to move the clamps back from the hose ends.
• Remove the hose from the radiator end first, then the engine end, using slip-joint pliers to help twist if needed.
• Keep the drain pan (at least 2-gallon) directly under the hose—more coolant will spill than the upper hose.

Step 6: Clean the sealing surfaces

• Wipe the radiator neck and engine fitting clean using shop towels.
• Remove any stuck rubber pieces carefully with a pick tool.

Step 7: Install the new hose and clamps

• Slide the clamps onto the new hose before installing the hose, using your hands.
• Push the hose fully onto each fitting until it bottoms out.
• Position clamps behind the raised “bead” on the fitting using hose clamp pliers.
• If you’re using screw-type clamps, tighten evenly using the correct socket or driver you have; do not crush the hose.
• Clamps should be snug, not hose-cutting tight.

Step 8: Reinstall the splash shield (if removed)

• Reinstall the under cover using a trim clip removal tool (to align clips) and 10mm socket.

Step 9: Refill coolant (Toyota pink)

• Insert a funnel into the radiator fill neck.
• Refill using Toyota Super Long Life Coolant (pink) premixed until full.
• Fill the overflow reservoir to the “FULL” line.

Step 10: Bleed air and verify no leaks

• Start the engine and let it idle with the radiator cap off; monitor level using a work light.
• Turn the heater to HOT; watch for warm air from vents.
• As the thermostat opens, coolant level may drop—add coolant with the funnel as needed.
• Once bubbles reduce and the level stabilizes, reinstall the radiator cap by hand.

---

✅ After Repair

• Check for leaks around both hose ends while idling, using a work light.
• Test drive 10–15 minutes, then let it cool and recheck the reservoir level; top off if needed.
• If the temperature gauge rises abnormally, stop and shut off—air may still be trapped.

---

💰 DIY vs Shop Cost

Shop Cost: $250-$550 (parts + labor)

DIY Cost: $50-$180 (parts only)

You Save: $200-$370 by doing it yourself!

Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 1.0-2.0 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.