🔧 Altima - Timing Belt Replacement

Your Altima’s 3.5L V6 does not have a timing belt. It uses an internal timing chain, so there is no scheduled timing belt replacement procedure.

If you are trying to fix timing noise, rattling on startup, cam/crank timing codes, or guide wear, the correct repair is timing chain replacement. This is a major engine repair and is not recommended as a first DIY job unless you have strong tool access and help.

Difficulty Level: Advanced | Estimated Time: 10-14 hours

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⚠️ Safety & Precautions

• ⚠️ Incorrect engine timing can cause serious engine damage.
• ⚠️ Disconnect the negative battery cable before starting.
• ⚠️ Support the engine before removing the right-side engine mount.
• ⚠️ Let the engine cool completely before draining coolant or removing covers.
• ⚠️ Do not rotate the crankshaft or camshafts separately after the timing chains are removed.

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🔧 Required Tools

You'll need the following tools for this repair:

• 10mm socket
• 12mm socket
• 14mm socket
• 17mm socket
• 19mm socket
• 21mm socket
• 22mm socket
• 3/8-inch drive ratchet
• 1/2-inch drive breaker bar
• 1/4-inch drive torque wrench
• 1/2-inch drive torque wrench
• Socket extension set
• Serpentine belt tool
• Crankshaft pulley holding tool (specialty)
• Harmonic balancer puller (specialty)
• Engine support bar (specialty)
• Floor jack
• Jack stands
• Drain pan
• Plastic scraper
• Gasket scraper
• Needle-nose pliers
• Trim clip removal tool
• Paint marker
• Safety glasses
• Nitrile gloves

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🔩 Required Parts

HowToo sells all the parts you need for this repair:

• Timing chain kit - Qty: 1
• Timing chain guides - Qty: 1 set
• Timing chain tensioners - Qty: 1 set
• Front timing cover gasket/sealant set - Qty: 1
• Valve cover gaskets - Qty: 2
• Front crankshaft oil seal - Qty: 1
• RTV silicone gasket maker - Qty: 1 tube
• Serpentine belt - Qty: 1
• Engine oil - Qty: 5 quarts
• Oil filter - Qty: 1
• Engine coolant - Qty: As needed

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📋 Before You Begin

• ✅ Park your Altima on level ground, shift to Park, and apply the parking brake.
• ✅ A timing chain is a metal chain that keeps the crankshaft and camshafts synchronized.
• ✅ A harmonic balancer puller safely removes the crankshaft pulley without prying.
• ✅ An engine support bar holds the engine from above when a mount is removed.
• ✅ Disconnect the negative battery cable with a 10mm socket.
• ✅ Raise the front with a floor jack and support it with jack stands.
• ✅ Drain engine oil and some coolant into a drain pan.

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🔨 Step-by-Step Instructions

Follow these steps in order:

Step 1: Remove Intake Parts and Engine Cover

• Use a 10mm socket to remove the plastic engine cover fasteners.
• Use needle-nose pliers to release small hose clamps.
• Use a 10mm socket to loosen intake duct clamps and remove the duct.
• Take photos before unplugging anything.

Step 2: Remove Wheel and Splash Shield

• Use a floor jack to lift the front of the vehicle.
• Place jack stands under the proper front support points.
• Use a 21mm socket to remove the right front wheel.
• Use a trim clip removal tool and 10mm socket to remove the splash shield.
• Reinstall wheel lug nuts later to Torque to 113 Nm (83 ft-lbs).

Step 3: Remove Serpentine Belt

• Use a serpentine belt tool to rotate the belt tensioner.
• Slide the belt off the pulleys by hand.
• Release the tensioner slowly.
• Draw the belt route first.

Step 4: Support Engine and Remove Right Mount

• Install the engine support bar across the upper body structure.
• Apply light upward tension to the engine lifting point.
• Use a 14mm socket and 17mm socket to remove the right engine mount and bracket.
• On reassembly, tighten engine mount fasteners to Torque to 62-83 Nm (46-61 ft-lbs) depending on bolt location.

Step 5: Remove Crankshaft Pulley

• Install the crankshaft pulley holding tool.
• Use a 22mm socket and 1/2-inch drive breaker bar to loosen the crankshaft pulley bolt.
• Use the harmonic balancer puller to pull the pulley straight off.
• Do not pry on the timing cover.
• On installation, tighten the crank bolt to Torque to 44 Nm (33 ft-lbs), then turn 84-90 degrees.

Step 6: Remove Valve Covers

• Use a 10mm socket to remove ignition coil bolts.
• Move the coils aside carefully.
• Use a 10mm socket to remove valve cover bolts.
• Lift off both valve covers.
• On reassembly, tighten valve cover bolts to Torque to 8-10 Nm (71-89 in-lbs).

Step 7: Remove Front Timing Cover

• Use 10mm socket, 12mm socket, and 14mm socket to remove timing cover bolts.
• Use a paint marker or cardboard to track bolt locations.
• Use a plastic scraper to separate the cover at the factory pry points.
• Do not scratch the aluminum sealing surfaces.

Step 8: Set Engine to Top Dead Center

• Use a 22mm socket to rotate the crankshaft clockwise only.
• Align the crankshaft and camshaft timing marks.
• Use a paint marker to mark chain-to-sprocket positions before removal.
• Top Dead Center means piston number 1 is at the top of its stroke.

Step 9: Remove Old Chains, Guides, and Tensioners

• Use a 10mm socket and 12mm socket to remove chain tensioners.
• Use a 10mm socket to remove timing chain guides.
• Remove the timing chains by hand after tension is released.
• Do not turn camshafts or crankshaft with the chains removed.

Step 10: Install New Timing Chain Kit

• Match the colored chain links to the crankshaft and camshaft timing marks.
• Use a 10mm socket to install new guides.
• Use a 10mm socket and 12mm socket to install new tensioners.
• Tighten guide and tensioner bolts to Torque to 9-12 Nm (80-106 in-lbs).
• Pull tensioner retaining pins only after all marks are verified.

Step 11: Verify Timing by Hand

• Use a 22mm socket to rotate the crankshaft clockwise two full turns.
• Stop immediately if the engine hits a hard stop.
• Return to Top Dead Center and recheck all timing marks.
• Never force engine rotation.

Step 12: Reseal and Reinstall Timing Cover

• Use a plastic scraper and gasket scraper to clean sealing surfaces.
• Apply RTV silicone gasket maker in the factory-style bead pattern.
• Install the front crankshaft oil seal.
• Use 10mm socket, 12mm socket, and 14mm socket to reinstall cover bolts.
• Tighten small cover bolts to Torque to 9-12 Nm (80-106 in-lbs).
• Tighten larger cover bolts to Torque to 20-25 Nm (15-18 ft-lbs).

Step 13: Reinstall Covers, Pulley, Mount, and Belt

• Use a 10mm socket to reinstall valve covers with new gaskets.
• Use the crankshaft pulley holding tool, 22mm socket, and 1/2-inch drive torque wrench to reinstall the crankshaft pulley.
• Use 14mm socket and 17mm socket to reinstall the engine mount.
• Use the serpentine belt tool to reinstall the serpentine belt.

Step 14: Refill Fluids and Start Engine

• Install the new oil filter and refill engine oil.
• Refill coolant.
• Use a 10mm socket to reconnect the negative battery cable.
• Start the engine and let it idle while checking for leaks.
• Shut it off immediately if you hear loud knocking, scraping, or heavy rattling.

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✅ After Repair

• ✅ Check for oil leaks around the timing cover, valve covers, and crankshaft seal.
• ✅ Check coolant level after the engine warms up and cools back down.
• ✅ Watch the temperature gauge during the first drive.
• ✅ If the check engine light turns on, scan for trouble codes before driving farther.
• ✅ Recheck oil and coolant levels the next day.

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💰 DIY vs Shop Cost

Shop Cost: $2,000-$3,500+ parts + labor

DIY Cost: $350-$900 parts only

You Save: $1,100-$2,600 by doing it yourself!

Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 10-14 hours.

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🎯 Ready to get started?

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