🔧 Highlander - Water Pump Replacement

Replacing the engine water pump on your Highlander requires draining the cooling system, removing the drive belt and pump, then refilling and bleeding the Toyota hybrid cooling system. The water pump circulates coolant through the engine, so leaks, bearing noise, or overheating are common reasons to replace it.

Difficulty Level: Advanced | Estimated Time: 3-5 hours

---

⚠️ Safety & Precautions

• ⚠️ Work only on a completely cool engine. Hot coolant can cause severe burns.
• ⚠️ Your Highlander is a hybrid. Do not touch orange high-voltage cables or hybrid components.
• ⚠️ Disconnect the 12V negative battery terminal before working near the engine drive belt.
• ⚠️ Support the vehicle with jack stands if you raise it. Never rely on a jack alone.
• ⚠️ Keep coolant away from pets and children. It is poisonous and tastes sweet.
• ⚠️ Use Toyota-approved coolant only. Mixing coolant types can damage the cooling system.

---

🔧 Required Tools

You'll need the following tools for this repair:

• 10mm socket
• 12mm socket
• 14mm socket
• 3/8-inch ratchet
• 3/8-inch torque wrench
• 3/8-inch breaker bar
• Serpentine belt tool (specialty)
• Flat-blade screwdriver
• Trim clip removal tool
• Pliers
• Drain pan 2-gallon minimum
• Coolant funnel kit with radiator adapter (specialty)
• Plastic scraper
• Shop towels
• Floor jack rated 3-ton minimum
• Jack stands rated 3-ton minimum
• Wheel chocks
• Nitrile gloves
• Safety glasses

---

🔩 Required Parts

HowToo sells all the parts you need for this repair:

• Engine mechanical water pump - Qty: 1
• Water pump gasket/O-ring - Qty: 1
• Toyota Super Long Life Coolant 50/50 pink premix - Qty: 2 gallons
• Serpentine drive belt - Qty: 1

---

📋 Before You Begin

• Park your Highlander on level ground and let the engine cool fully.
• Set the parking brake and place wheel chocks behind the rear wheels.
• Open the hood and remove the key fob from the vehicle so the hybrid system cannot be made READY accidentally.
• Disconnect the 12V negative battery cable using a 10mm socket. The 12V battery powers normal electronics and relays.
• If lifting the front, use a floor jack rated 3-ton minimum and support the vehicle with jack stands rated 3-ton minimum.
• Assumption: This procedure is for the engine-driven mechanical water pump, not the hybrid inverter electric coolant pump.

---

🔨 Step-by-Step Instructions

Follow these steps in order:

Step 1: Remove the Engine Covers and Lower Splash Shield

• Put on safety glasses and nitrile gloves.
• Use a 10mm socket to remove the upper engine cover fasteners if equipped.
• Raise the front of your Highlander with a floor jack rated 3-ton minimum.
• Place jack stands rated 3-ton minimum under the front support points.
• Use a 10mm socket, flat-blade screwdriver, and trim clip removal tool to remove the lower splash shield.
• Keep clips grouped by location.

Step 2: Drain the Engine Coolant

• Place a drain pan 2-gallon minimum under the radiator drain area.
• Slowly remove the coolant reservoir cap by hand only after the engine is cold.
• Use pliers or a flat-blade screwdriver as needed to open the radiator drain cock.
• Let the coolant drain fully into the pan.
• Close the drain cock gently by hand. Do not overtighten plastic drain parts.

Step 3: Remove the Serpentine Drive Belt

• Take a photo of the belt routing before removal.
• A serpentine belt is the long belt that turns accessories on the front of the engine.
• Use a serpentine belt tool (specialty) or 3/8-inch breaker bar on the belt tensioner.
• Rotate the tensioner to release belt tension, then slide the belt off the pulleys.
• Slowly release the tensioner. Do not let it snap back.
• Remove the belt from the engine bay.

Step 4: Access the Water Pump

• The water pump is mounted on the front side of the V6 engine and is driven by the serpentine belt.
• Use a 10mm socket or 12mm socket to remove any small brackets or shields blocking the pump.
• Use shop towels to catch coolant that may spill when hoses or the pump are removed.
• If a coolant hose blocks access, use pliers to compress the spring clamp and slide it back.
• Twist the hose gently by hand before pulling it off. Do not pry hard on plastic fittings.

Step 5: Remove the Water Pump

• Use a 12mm socket or 14mm socket to loosen the water pump mounting bolts evenly.
• Remove the bolts and note their locations. Some bolts may be different lengths.
• Pull the water pump straight away from the engine.
• If it is stuck, tap gently by hand or wiggle it. Do not gouge the aluminum engine surface.
• Expect more coolant to drain. Keep the drain pan 2-gallon minimum underneath.

Step 6: Clean the Sealing Surface

• Use a plastic scraper to remove old gasket material from the engine surface.
• Use shop towels to wipe the area clean and dry.
• Do not use a metal scraper. Aluminum scratches easily and can cause leaks.
• Check that no old gasket pieces fall into the coolant passage.

Step 7: Install the New Water Pump

• Install the new water pump gasket/O-ring onto the new pump.
• Position the new engine mechanical water pump against the engine by hand.
• Start all bolts by hand first to prevent cross-threading.
• Use a 12mm socket or 14mm socket to snug the bolts in a crisscross pattern.
• Use a 3/8-inch torque wrench to tighten the water pump bolts to Torque to 21 Nm (15 ft-lbs).
• Even tightening prevents leaks.

Step 8: Reinstall Hoses, Brackets, and Belt

• Reconnect any coolant hoses by hand and move spring clamps back into position using pliers.
• Reinstall any brackets or shields using a 10mm socket or 12mm socket.
• Use the belt routing photo to install the new serpentine drive belt.
• Use the serpentine belt tool (specialty) or 3/8-inch breaker bar to rotate the tensioner.
• Slide the belt over the final pulley, then slowly release the tensioner.
• Check every pulley groove. The belt must sit straight and fully seated.

Step 9: Refill the Cooling System

• Install a coolant funnel kit with radiator adapter (specialty) at the coolant fill point.
• A spill-free funnel holds coolant above the radiator and helps air bubbles escape.
• Slowly add Toyota Super Long Life Coolant 50/50 pink premix.
• Fill until the funnel level stays steady and the reservoir is at the FULL mark.
• Check under the water pump with safety glasses on and look for leaks.

Step 10: Bleed Air from the Cooling System

• Reconnect the 12V negative battery cable using a 10mm socket.
• Make sure the transmission is in Park and the parking brake is set.
• Start your Highlander and let the engine run as needed while watching the coolant funnel.
• Set cabin heat to maximum temperature and low fan speed.
• Add coolant as the level drops. Air bubbles should rise into the funnel.
• When warm air comes from the vents and bubbles stop, install the cap.
• Use a 10mm socket to reinstall the lower splash shield and upper covers.

---

✅ After Repair

• Start your Highlander and inspect the water pump area for leaks.
• Watch the temperature gauge during the first drive. Stop immediately if it rises above normal.
• After the engine cools completely, recheck coolant level and top off with Toyota Super Long Life Coolant 50/50 pink premix.
• Listen for belt squeal or chirping. If heard, recheck belt routing and pulley alignment.
• Dispose of old coolant at a proper recycling facility. Do not pour it on the ground or into a drain.
• For the next few days, check for pink coolant spots under the front of your Highlander.

---

💰 DIY vs Shop Cost

Shop Cost: $650-$1,050 (parts + labor)

DIY Cost: $180-$350 (parts only)

You Save: $470-$700 by doing it yourself!

Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 3-4 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.