🔧 Timing Belt - Replacement

The 4.0L V6 in your Tacoma uses a timing belt that should be replaced on schedule, along with the tensioner and idler components. Many owners also replace the water pump at the same time because access is already open and the labor overlaps.

Difficulty Level: Advanced | Estimated Time: 6-8 hours

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⚠️ Safety & Precautions

• Disconnect the negative battery cable before starting.
• Let the engine cool completely before removing belts or hoses.
• Support the truck securely on jack stands before working underneath.
• Do not rotate the crankshaft or camshafts with the timing belt removed.
• Keep fingers clear when releasing the belt tensioner.
• If you replace the water pump, have fresh coolant ready for refill and bleeding.

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🔧 Required Tools

You'll need the following tools for this repair:

• 10mm socket
• 12mm socket
• 14mm socket
• 17mm socket
• 21mm socket
• Ratchet
• Long breaker bar
• Torque wrench
• Harmonic balancer puller (specialty)
• Serpentine belt tool
• Screwdriver set
• Floor jack (rated 3-ton minimum)
• Jack stands
• Drain pan
• Funnel
• Paint marker
• Safety glasses
• Mechanic gloves

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🔩 Required Parts

HowToo sells all the parts you need for this repair:

• Timing belt kit - Qty: 1
• Timing belt tensioner - Qty: 1
• Timing belt idler pulleys - Qty: 2
• Water pump - Qty: 1
• Water pump gasket - Qty: 1
• Coolant - Qty: 1 refill
• Accessory drive belt - Qty: 1
• Camshaft seals - Qty: 2
• Crankshaft seal - Qty: 1
• Thermostat gasket - Qty: 1

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📋 Before You Begin

• Park on level ground and set the parking brake.
• Disconnect the negative battery cable.
• Raise the front of the truck and support it securely on jack stands.
• Drain the coolant into a clean pan if replacing the water pump.
• Rotate the engine by hand only, using a socket on the crank bolt.

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🔨 Step-by-Step Instructions

Follow these steps in order:

Step 1: Remove the accessory drive belt

• Use the serpentine belt tool to relieve tension.
• Slip the belt off the pulleys and remove it from the engine bay.
• Take a photo before removal.

Step 2: Remove the fan shroud and radiator fan assembly

• Use a 10mm socket to remove the upper shroud bolts.
• Lift the shroud and fan assembly carefully out of the engine bay.
• If needed, remove the fan clutch nuts with a 12mm socket.

Step 3: Remove the crankshaft pulley

• Use a 21mm socket and breaker bar to loosen the crank bolt.
• Remove the crank pulley with a harmonic balancer puller (specialty) if it is stuck.
• Torque on reassembly: 245 Nm (181 ft-lbs).

Step 4: Remove the timing covers

• Use a 10mm socket to remove the upper and lower timing cover bolts.
• Remove the covers and set them aside in order.

Step 5: Set the engine to top dead center

• Use a 21mm socket on the crank bolt to rotate the engine clockwise only.
• Align the timing marks on the crankshaft and camshaft pulleys.
• Verify the marks match the engine’s factory timing positions before removing the belt.
• Mark everything with paint first.

Step 6: Remove the belt tensioner and idlers

• Use a 12mm socket to remove the tensioner bolts.
• Use a 14mm socket to remove the idler pulley bolts.
• Remove the tensioner and pulleys from the engine.
• Torque on reassembly: 39 Nm (29 ft-lbs) for idlers; 19 Nm (14 ft-lbs) for tensioner bolts.

Step 7: Remove the timing belt

• Slide the timing belt off the sprockets by hand.
• Do not let the camshafts rotate once the belt is off.

Step 8: Replace the water pump and seals if included

• Use a 10mm socket to remove the water pump bolts.
• Remove the old pump and gasket.
• Install the new pump with the new gasket.
• Torque to 10 Nm (89 in-lbs) unless your kit specifies otherwise.
• Replace camshaft and crankshaft seals if they are leaking.

Step 9: Install the new timing belt

• Make sure the timing marks still line up.
• Route the new belt around the sprockets in the same path as the old one.
• Keep the belt tight on the non-tensioned side while installing.
• Install the new tensioner and idlers.

Step 10: Set belt tension

• Use the new tensioner to apply belt tension.
• Check that all timing marks still align after tension is set.
• Rotate the engine by hand two full turns clockwise with a 21mm socket.
• Recheck all marks again.

Step 11: Reassemble the front of the engine

• Install the timing covers with a 10mm socket.
• Install the crank pulley and torque the crank bolt to 245 Nm (181 ft-lbs).
• Reinstall the fan assembly and shroud with a 10mm socket.
• Reinstall the accessory belt and set proper tension.

Step 12: Refill and bleed coolant if the water pump was replaced

• Use a funnel to refill with the correct coolant mix.
• Bleed air from the cooling system as needed.
• Inspect for leaks at the pump, hoses, and drain plugs.

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✅ After Repair

• Start the engine and listen for abnormal noises.
• Check belt tracking and verify the engine idles smoothly.
• Watch coolant temperature and inspect for leaks after warm-up.
• Recheck coolant level after the first drive.
• Replace the timing belt again at the factory service interval.

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💰 DIY vs Shop Cost

Shop Cost: $1,100-$1,800 (parts + labor)

DIY Cost: $300-$650 (parts only)

You Save: $500-$1,400 by doing it yourself!

Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 6-8 hours.

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🎯 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.