🔧 Highlander - Water Pump Replacement

On your Highlander’s 3.5L V6, the water pump circulates coolant through the engine and radiator. If the pump is leaking (coolant drip from the pump area) or the bearing is failing (growling noise), replacement is the correct fix to prevent overheating.

Difficulty Level: Advanced | Estimated Time: 4-7 hours

---

⚠️ Safety & Precautions

• ⚠️ Never open the coolant system hot; wait until fully cool.
• ⚠️ Support the vehicle with jack stands; never rely on a jack.
• ⚠️ Keep coolant off belts and pulleys; it can cause belt slip.
• ⚠️ Coolant is toxic—use a drain pan and clean spills immediately.
• ⚠️ Disconnect the negative battery terminal if your hands/tools will be near the alternator/main power cable.

---

🔧 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
• Drain pan (at least 10-quart)
• Funnel
• Spill-free funnel kit (specialty)
• Shop towels
• Plastic trim clip removal tool
• Ratchet (3/8" drive)
• Ratchet (1/2" drive)
• Socket set 8mm-19mm (metric)
• Wrench set 10mm-19mm (metric)
• Torque wrench 10-80 Nm
• Torque wrench 40-200 Nm
• Serpentine belt tool 3/8" drive
• Flathead screwdriver
• Pliers
• Gasket scraper (plastic)

---

🔩 Required Parts

HowToo sells all the parts you need for this repair:

• Water pump assembly (3.5L V6) - Qty: 1
• Water pump gasket / O-ring (as equipped) - Qty: 1
• Toyota Super Long Life Coolant (pink, premixed) - Qty: 2-3 gallons
• Serpentine drive belt - Qty: 1
• Hose clamp (replacement style, if originals are weak) - Qty: 1-2

---

📋 Before You Begin

• Park on level ground, set the parking brake, and chock the rear wheels.
• Let the engine cool completely (cold to the touch).
• Raise the front-right corner with a floor jack and support with jack stands.
• Remove the front-right wheel using the lug wrench and keep the lug nuts together.
• Tip: Take photos before disconnecting hoses.

---

🔨 Step-by-Step Instructions

Follow these steps in order:

Step 1: Drain the coolant

• Place a drain pan (at least 10-quart) under the radiator.
• Open the radiator cap slowly (engine cold) to release any remaining pressure.
• Open the radiator drain cock using a pliers or by hand (as equipped) and drain coolant.
• Close the drain cock once finished.

Step 2: Remove the right-side splash shield for access

• Remove the right front fender liner/splash shield fasteners using a plastic trim clip removal tool and 10mm socket.
• Fold the liner back to expose the accessory belt area.

Step 3: Remove the serpentine drive belt

• Locate the belt tensioner.
• Rotate the tensioner using a serpentine belt tool 3/8" drive to relieve tension, then slip the belt off a pulley.
• Remove the belt from all pulleys and set it aside.
• Tip: Sketch the belt routing before removal.

Step 4: Remove components blocking the water pump (as equipped)

• Remove any brackets or covers limiting access using a 10mm socket and 12mm socket.
• If a coolant hose is attached to the pump area, release the clamp using pliers and twist the hose gently to break it free.
• Plug the hose end with a clean shop towel to reduce spills.

Step 5: Remove the water pump

• Place the drain pan (at least 10-quart) under the pump area; more coolant will spill.
• Remove the water pump mounting bolts using a 10mm socket (some locations may use 12mm socket depending on fastener).
• Pull the water pump straight off the engine.
• Remove the old gasket / O-ring and discard it.

Step 6: Clean the sealing surface

• Clean the engine’s water pump sealing surface using a gasket scraper (plastic) and shop towels.
• Do not gouge the aluminum surface; it must be smooth and clean.

Step 7: Install the new water pump

• Install the new gasket / O-ring onto the new pump (match the original orientation).
• Position the pump on the engine and start all bolts by hand using a 10mm socket to avoid cross-threading.
• Tighten bolts evenly in a crisscross pattern using a torque wrench 10-80 Nm.
• Torque to 10 Nm (89 in-lbs) for the water pump mounting bolts.

Step 8: Reinstall removed hoses, brackets, and the belt

• Reconnect any coolant hose(s) and secure clamps using pliers.
• Reinstall brackets/covers using a 10mm socket and 12mm socket (tighten snug, then final tighten with a torque wrench if you have the factory spec available).
• Install the serpentine belt using the serpentine belt tool 3/8" drive and confirm it is seated in every pulley groove.

Step 9: Reinstall splash shield and wheel

• Reinstall the fender liner fasteners using a plastic trim clip removal tool and 10mm socket.
• Reinstall the wheel using a socket set 8mm-19mm (metric).
• Lower the vehicle from the jack stands using the floor jack.

Step 10: Refill and bleed the cooling system

• Fill the radiator with Toyota Super Long Life Coolant (pink, premixed) using a funnel or spill-free funnel kit (specialty).
• Fill the coolant reservoir to the “FULL” line.
• Start the engine and set the heater to HOT (this helps move coolant through the heater core).
• Let the engine idle and watch the coolant level; add coolant as the level drops.
• When the radiator fan cycles and heat is steady, shut the engine off and let it cool completely, then recheck and top off as needed.

---

✅ After Repair

• Check for leaks around the water pump and hose connections with the engine running.
• Verify the temperature gauge stays normal during a 10-15 minute test drive.
• Recheck coolant level the next day (cold engine) and top off the reservoir if needed.
• If any warning lights appear or it overheats, stop driving and recheck belt routing and coolant level.

---

💰 DIY vs Shop Cost

Shop Cost: $800-$1,400 (parts + labor)

DIY Cost: $180-$450 (parts only)

You Save: $620-$950 by doing it yourself!

Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 4-7 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.