Acura TL 2004-2008 3.5L Engine Bolt Torque Specifications & Fastener Values
Acura TL 2004-2008

Acura TL 2004-2008 3.5L Engine Bolt Torque Specifications

This page provides detailed torque specifications for various bolts on the 3.5L V6 engine found in the 2004-2008 Acura TL. Includes cylinder head, intake manifold, exhaust manifold, and other critical engine component bolt torques.

Updated

Important Information

Safety guidelines and reference information for proper torque application

Quick Reference Guide
ft-lbs → Nm
× 1.356
ft-lbs → kg-m
× 0.138
Nm → ft-lbs
× 0.738
in-lbs → ft-lbs
× 0.083

Common Torque Patterns

Star Pattern

Used for wheels and other circular bolt patterns

Star Pattern torque pattern diagram showing proper bolt tightening sequence
Cross Pattern

Used for gaskets and cover plates

Cross Pattern torque pattern diagram showing proper bolt tightening sequence
Sequential Pattern

Used for head bolts and other critical components

Sequential Pattern torque pattern diagram showing proper bolt tightening sequence

Common Mistakes to Avoid

Over-tightening

Exceeding the specified torque value can stretch or break fasteners, damage threads, or crack components.

Prevention:

Always use a calibrated torque wrench and follow specifications exactly.

Incorrect Torque Sequence

Tightening bolts in the wrong order can cause uneven pressure distribution and potential leaks or damage.

Prevention:

Follow the manufacturer's specified torque sequence pattern.

Dirty Threads

Dirt, rust, or old thread locker can affect torque readings and proper fastener tension.

Prevention:

Clean and inspect all threads before assembly. Use new thread locker if specified.

Reusing TTY Bolts

Torque-to-yield bolts are designed to stretch and must not be reused.

Prevention:

Always replace TTY bolts with new ones. They are single-use only.

Dry vs. Lubricated

Not accounting for whether torque specs are for dry or lubricated fasteners can lead to incorrect tension.

Prevention:

Check if specs are for dry or lubricated threads. Use specified lubricant when required.

Recommended Tools

Torque Wrench (1/4" Drive)

Range: 2-25 ft-lbs
Small fasteners, delicate components

Torque Wrench (3/8" Drive)

Range: 10-100 ft-lbs
Most common automotive fasteners

Torque Wrench (1/2" Drive)

Range: 30-250 ft-lbs
Large fasteners, wheels

Angle Gauge

Torque-to-yield (TTY) bolts

Torque Wrench Care

  • Calibrate annually or after 5,000 clicks
  • Store at lowest setting
  • Keep clean and lubricated

Search Specifications

Search by component name, bolt size, or description

Torque Calculator

Convert between different torque units

3.5l-engine Cylinder Head

Torque specifications for the cylinder head and related components.

1

Cylinder Head Bolts

M11 x 1.25 (Estimated)
Important Notes
Cylinder head bolts are tightened in multiple stages. An angle torque is required after the initial torque value. Consult the service manual for the precise angle specification. Estimated bolt size.
2

Valve Cover Bolts

M6 x 1.0
Torque Value
7 ft-lbs (10 N·m)
Important Notes
These bolts secure the valve cover to the cylinder head.
3

Rocker Arms/Shafts Bolts

M8 x 1.25
Torque Value
16 ft-lbs (22 N·m)
Important Notes
These bolts secure the rocker arm assembly to the cylinder head.
4

Spark Plugs

M14 x 1.25 (Thread Size, not bolt)
Torque Value
13 ft-lbs (18 N·m)
Important Notes
This is the torque specification for spark plug installation. Be careful not to overtighten.
5

Ignition Coil Bolts

M6 x 1.0
Torque Value
8 ft-lbs (11 N·m)
Important Notes
These bolts secure the ignition coils to the cylinder head or valve cover.
6

Exhaust Manifold/Headers to Cylinder Head Bolts

M8 x 1.25
Torque Value
16 ft-lbs (22 N·m)
Important Notes
These bolts secure the exhaust manifold/headers to the cylinder head. Note that some service manuals may have an earlier torque value, then a final tightening after an engine warm up cycle.

3.5l-engine Block

Torque specifications for engine block components.

1

Main Bearing Bolts

M10 x 1.5 (Estimated)
Important Notes
Main bearing bolts are tightened in multiple stages. An angle torque is required after the initial torque value. Consult the service manual for the precise angle specification. Estimated bolt size.
2

Connecting Rod Nuts

M9 x 1.25 (Estimated)
Torque Value
20 ft-lbs (27 N·m)
Important Notes
These nuts secure the connecting rod caps to the connecting rods. Estimated bolt size.
3

Oil Pan Bolts

M6 x 1.0
Torque Value
7 ft-lbs (10 N·m)
Important Notes
These bolts secure the oil pan to the engine block.
4

Water Pump Bolts

M8 x 1.25
Torque Value
16 ft-lbs (22 N·m)
Important Notes
These bolts secure the water pump to the engine block.
5

Oil Drain Plug Bolt

M14 x 1.5
Torque Value
29 ft-lbs (39 N·m)
Important Notes
This bolt seals the oil drain hole in the oil pan.
6

Starter Motor Mounting Bolts

M10 x 1.5
Torque Value
33 ft-lbs (45 N·m)
Important Notes
These bolts secure the starter motor to the engine block or transmission bellhousing.

3.5l-engine Timing

Torque specifications for the timing system components.

1

Timing Belt/Chain Tensioner Bolt

M8 x 1.25
Torque Value
33 ft-lbs (45 N·m)
Important Notes
This bolt secures the timing belt tensioner.
2

Camshaft Sprocket Bolt

M10 x 1.25
Torque Value
22 ft-lbs (30 N·m)
Important Notes
These bolts secure the camshaft sprockets to the camshafts.

3.5l-engine Induction

Torque specifications for the intake system components.

1

Throttle Body Bolts

M6 x 1.0
Torque Value
16 ft-lbs (22 N·m)
Important Notes
These bolts secure the throttle body to the intake manifold.
2

Intake Manifold Bolts

M8 x 1.25
Torque Value
16 ft-lbs (22 N·m)
Important Notes
These bolts attach the intake manifold to the cylinder head.
3

EGR Valve Bolts

M6 x 1.0
Torque Value
16 ft-lbs (22 N·m)
Important Notes
These bolts secure the EGR valve to the intake manifold, cylinder head, or exhaust manifold.
4

Fuel Rail Bolts

M6 x 1.0
Torque Value
16 ft-lbs (22 N·m)
Important Notes
These bolts attach the fuel rail to the intake manifold or cylinder head.
5

Fuel Injector Rail Bolts

M6 x 1.0
Torque Value
7 ft-lbs (10 N·m)
Important Notes
These bolts secure the fuel injector rail to the intake manifold.
6

Fuel Injector Bolts

M6 x 1.0
Torque Value
7 ft-lbs (10 N·m)
Important Notes
These bolts secure the fuel injectors to the intake manifold or fuel rail.

3.5l-engine Cooling

Torque specifications for cooling system components.

1

Water Pump Pulley Bolts

M6 x 1.0
Torque Value
16 ft-lbs (22 N·m)
Important Notes
These bolts secure the water pump pulley to the water pump itself.
2

Thermostat Housing Bolts

M6 x 1.0
Torque Value
7 ft-lbs (10 N·m)
Important Notes
These bolts secure the thermostat housing to the engine block or cylinder head.

3.5l-engine Accessories

Torque specifications for engine accessory mounting components.

1

Crankshaft Pulley/Harmonic Balancer Bolt

M14 x 1.5 (Estimated)
Torque Value
181 ft-lbs (245 N·m)
Important Notes
This bolt secures the crankshaft pulley/harmonic balancer to the crankshaft. Estimated bolt size.
2

Alternator Mounting Bolts

M10 x 1.5
Torque Value
33 ft-lbs (45 N·m)
Important Notes
These bolts secure the alternator to the engine block or bracket.
3

A/C Compressor Mounting Bolts

M10 x 1.5
Torque Value
33 ft-lbs (45 N·m)
Important Notes
These bolts secure the A/C compressor to the engine block or bracket.
4

Crankshaft Position Sensor Bolt

M6 x 1.0
Torque Value
7 ft-lbs (10 N·m)
Important Notes
This is the recommended torque for a crankshaft position sensor bolt. Estimated bolt size.

3.5l-engine Other

Torque specifications for other components.

1

Flywheel Bolts

M10 x 1.25 (Estimated)
Torque Value
76 ft-lbs (103 N·m)
Important Notes
These bolts attach the flywheel to the crankshaft. Estimated bolt size.
2

Oil Filter Housing Bolt

N/A (Hand Tight)
Torque Value
0 ft-lbs (0 N·m)
Important Notes
Oil filter housings are typically hand tight. Do not use a torque wrench.

Troubleshooting Guide

Common issues, diagnostic steps, and prevention guidelines

Common Issues

Bolt stretching, stripped threads, uneven torque patterns

Loose Components

Symptoms:
  • Rattling or vibration noises
  • Visible movement in components
  • Uneven panel gaps
Solutions:
  • Clean threads and mounting surfaces
  • Replace damaged fasteners
  • Apply proper torque in sequence
  • Use thread locker if specified

Stripped Fasteners

Symptoms:
  • Unable to achieve proper torque
  • Fastener spins freely
  • Visible thread damage
Solutions:
  • Use thread repair kit if appropriate
  • Install thread insert (HeliCoil)
  • Replace component if threaded hole is damaged
  • Upgrade to higher grade fastener if recommended

Overtightened Components

Symptoms:
  • Cracked or deformed parts
  • Broken fasteners
  • Compressed gaskets or seals
Solutions:
  • Replace damaged components
  • Use new fasteners
  • Follow proper torque sequence
  • Verify correct torque specifications

Diagnostic Steps

Visual inspection, torque verification, thread assessment

1

Visual Inspection

Inspect the affected area for any visible signs of damage or wear

  • Check for cracks or deformation
  • Look for signs of excessive wear
  • Verify proper fastener installation
2

Torque Verification

Verify the torque applied to the fasteners

  • Check the torque wrench calibration
  • Verify the torque specification
  • Compare the applied torque to the specification
3

Thread Assessment

Assess the condition of the threads

  • Check for signs of thread damage
  • Verify the thread type and size
  • Check for proper thread engagement

Prevention Guidelines

Best practices, maintenance tips, tool care

Best Practices

  • Always follow the recommended torque specification
  • Use the correct type and size of fasteners
  • Verify the torque wrench calibration regularly

Maintenance Tips

  • Regularly inspect the affected area for signs of wear or damage
  • Replace damaged or worn-out components promptly
  • Keep the work area clean and organized

Tool Care

  • Regularly clean and maintain the torque wrench
  • Store the torque wrench in a dry and secure location
  • Verify the torque wrench calibration before each use

Frequently Asked Questions

Find answers to common questions about torque specifications

Q1

Why are torque specifications important?

Using the correct torque ensures proper clamping force between components. Over-tightening can damage bolts, threads, or gaskets, leading to leaks or component failure. Under-tightening can result in loose connections, also causing leaks, vibrations, and potential part failure, which can be catastrophic in the 3.5L engine. Think of head bolts; incorrect torque here can lead to a blown head gasket.

Q2

Do I need a special tool to torque bolts?

Yes, a torque wrench is essential for achieving the correct torque. A regular wrench or socket will not provide accurate torque readings. Click-type torque wrenches are common for this application. For instance, tightening intake manifold bolts to 'hand tight' is insufficient and unreliable.

Q3

What should I do if a bolt feels like it's stripping?

Stop tightening immediately! If a bolt feels like it’s stripping, it means the threads are being damaged. You should carefully remove the bolt, inspect the threads, and if they are damaged, either chase the threads with the appropriate tap or die or replace the bolt. For internal engine bolts on the 3.5L, this is especially important to address and not ignore.

Q4

Can I reuse bolts?

It depends on the bolt and application. Some bolts, particularly those for connecting rod caps and cylinder heads on the 3.5L engine, are designed for single use (torque-to-yield) and should always be replaced. Others, like intake manifold bolts, can often be reused if they are in good condition. Always refer to the Acura service manual for specific bolt reuse guidelines. Replacing head bolts after a head gasket repair is vital for longevity and reliability.

Q5

What does 'torque to yield' mean?

Torque to yield (TTY) bolts are designed to stretch beyond their elastic limit when tightened. This ensures a more consistent clamping force. These bolts cannot be reused because they have been permanently deformed. Using new TTY bolts on critical components like the 3.5L's head and main bearing bolts is imperative for proper functionality.

Q6

Should I lubricate threads before torquing?

Lubricating threads can affect torque readings. Unless otherwise specified in the Acura service manual, do not lubricate threads on critical engine components like connecting rod or crankshaft bolts. However, where specified, use the exact lubricant recommended in the manual; incorrect lubrication will lead to incorrect torque and could damage engine components. Some fasteners may require threadlocker, which also acts as a lubricant and also requires different torquing methods.

Environmental Considerations

Temperature, humidity, and seasonal effects on torque specifications

Temperature Effects

Includes: High Heat, Cold Weather, Thermal Cycling

Temperature can significantly impact torque values and fastener behavior

Cold Weather

Effects:
  • Increased material brittleness
  • Higher torque required due to thread contraction
  • Reduced thread lubricant effectiveness
Recommendations:
  • Allow components to warm to room temperature when possible
  • Consider using winter-grade thread lubricants
  • Check torque values more frequently during winter months

Hot Weather

Effects:
  • Thermal expansion of components
  • Decreased friction in threads
  • Accelerated lubricant breakdown
Recommendations:
  • Check torque when components are at normal operating temperature
  • Use temperature-resistant thread lockers
  • Consider re-torquing after heat cycles

Humidity and Corrosion

Covers: Rust Prevention, Salt Exposure, Moisture Control

Moisture and corrosion can affect fastener integrity and torque values

High Humidity

Effects:
  • Accelerated corrosion formation
  • Reduced friction coefficient
  • Potential thread seizing
Prevention:
  • Use corrosion-resistant fasteners
  • Apply appropriate anti-seize compounds
  • Maintain proper protective coatings

Salt Exposure

Effects:
  • Rapid corrosion development
  • Thread damage
  • Seized fasteners
Prevention:
  • Regular underbody washing
  • Use of sacrificial anodes where appropriate
  • Application of protective coatings

Seasonal Maintenance

Spring, Summer, Fall, and Winter maintenance schedules

Spring

  • Inspect for winter damage
  • Clean and protect exposed fasteners
  • Check torque on critical components

Summer

  • Monitor heat-affected components
  • Check expansion-related loosening
  • Inspect cooling system mounts

Fall

  • Prepare for winter conditions
  • Apply corrosion protection
  • Verify all fasteners are properly torqued

Winter

  • More frequent inspection of critical fasteners
  • Check for salt damage
  • Monitor suspension component torque

Related Resources

Tools, service procedures, and technical bulletins

Recommended Tools

Torque Wrench (1/2" Drive)

A 1/2" drive torque wrench with a range covering 10-150 ft-lbs (or equivalent in Nm) is essential for accurately tightening bolts to specified torque values.

  • Accurate torque settings
  • Audible click when target torque is reached
Learn more

Torque Wrench (3/8" Drive)

A 3/8" drive torque wrench with a lower torque range of 5-80 ft-lbs (or equivalent in Nm) is necessary for smaller fasteners and components.

  • Accurate torque settings
  • Audible click when target torque is reached
Learn more

Socket Set (1/2" and 3/8" Drive)

A comprehensive socket set including standard and deep sockets in both 1/2" and 3/8" drive sizes to fit various bolt heads.

  • Variety of sizes
  • Durable construction
Learn more

Extension Bars (1/2" and 3/8" Drive)

Extension bars in both 1/2" and 3/8" drive sizes for accessing bolts in recessed or hard-to-reach areas.

  • Extends reach of socket
  • Secure connection
Learn more

Universal Joint (1/2" and 3/8" Drive)

A universal joint adapter allows for angled access to bolts when a straight approach is not possible.

  • Flexibility in socket positioning
  • Durable construction
Learn more
Service Procedures

Cylinder Head Installation

This procedure outlines the correct bolt torque sequence and specifications for installing the cylinder heads on the 3.5L engine.

  • Clean all mating surfaces of the cylinder block and heads.
  • Install new cylinder head gaskets.
  • Install the cylinder heads and loosely install bolts.
  • Torque cylinder head bolts in the specified sequence and stages (refer to service manual for specific sequence and torque values, typically involving multiple passes at different torque settings).
  • Verify all bolt torques are within specification after final sequence.
View full procedure

Intake Manifold Installation

Procedure for torquing the intake manifold bolts on the 3.5L engine.

  • Clean all mating surfaces of the cylinder head and intake manifold.
  • Install the intake manifold and loosely install bolts.
  • Torque intake manifold bolts in the specified sequence and stages (refer to service manual for specific sequence and torque values).
  • Verify all bolt torques are within specification after final sequence.
View full procedure

Oil Pan Installation

Procedure for torquing the oil pan bolts on the 3.5L engine.

  • Clean all mating surfaces of the engine block and oil pan.
  • Install the oil pan gasket and install the oil pan and loosely install bolts.
  • Torque the oil pan bolts in the specified sequence (refer to service manual for specific sequence and torque values).
  • Verify all bolt torques are within specification after final sequence.
View full procedure

Valve Cover Installation

Procedure for torquing the valve cover bolts on the 3.5L engine.

  • Clean all mating surfaces of the cylinder head and valve cover.
  • Install the valve cover gasket and install the valve cover and loosely install bolts.
  • Torque the valve cover bolts in the specified sequence (refer to service manual for specific sequence and torque values).
  • Verify all bolt torques are within specification after final sequence.
View full procedure
Technical Service Bulletins

Excessive Oil Consumption Due to Improper Cylinder Head Bolt Torque

2006-03-15

Some 2004-2006 Acura TL models with the 3.5L engine may experience excessive oil consumption due to improper cylinder head bolt torque. This bulletin provides updated torque specifications and tightening procedures to rectify the issue.

2004-2006

Resolution: Verify and, if necessary, re-torque cylinder head bolts to the updated specifications in the bulletin. Use a calibrated torque wrench and follow the specified torque sequence.

Intake Manifold Gasket Leakage Due to Improper Torque

2007-09-20

Some 2004-2007 Acura TL models with the 3.5L engine may experience intake manifold gasket leaks if the intake manifold bolts were not torqued to specification. This bulletin provides the proper torque specification to resolve the issue.

2004-2007

Resolution: Replace the intake manifold gasket and torque the intake manifold bolts to the specified values in the service manual. Ensure a proper tightening sequence is followed.

About the Author

Expert automotive knowledge and experience

Alan Montanye - Automotive Technical Specialist
ASE

Alan Montanye

Automotive Technical Specialist

ASE Master Certified Technician with over a decade of hands-on experience in automotive repair and diagnostics.

Facebook Contact
15+ Years
Experience
500+ Guides
Guides
50+ Makes
Vehicles
1000+ Solutions
Solutions

Diagnostic

Specialized in advanced diagnostic techniques using modern scan tools and oscilloscopes.

Repair

Expert in both traditional mechanical repairs and modern vehicle systems.

Additional Expertise

Documentation

Created over 500 detailed repair guides and technical documents.

Training

Conducted technical training sessions and contributed to repair databases.

Certifications & Research

Certifications

  • ASE Master Technician Certification
  • Advanced Diagnostic Specialist
  • Hybrid/Electric Vehicle Systems
  • Performance Tuning Expert

Research & Community

Actively researches emerging technologies and contributes to automotive forums.

Legal Disclaimer

Important information about using this content

Always refer to your vehicle's service manual and take appropriate safety precautions when performing any maintenance or repairs.

General Information
The information provided on this website is for general informational purposes only. While we strive to maintain accuracy in our content, all specifications, procedures, and technical information should be verified against your vehicle's official service manual or with the manufacturer directly.
Warranty & Liability

The content on this website is provided "as is" without any representations or warranties, express or implied. We make no representations or warranties regarding the accuracy, completeness, or availability of the information.

We shall not be liable for any direct, indirect, special, or consequential damages arising from the use of information on this website.

Technical Information
  • All specifications, including torque values, fluid capacities, and maintenance procedures, should be verified against your vehicle's factory service manual.
  • Vehicle specifications and procedures may vary by model year, trim level, and region.
  • Always follow the manufacturer's recommended procedures and safety precautions.
  • Working on vehicles can be dangerous. Always take proper safety precautions and use appropriate safety equipment.
  • If you're unsure about any procedure, consult a qualified professional mechanic.
Intellectual Property
All content, including text, images, and specifications, is protected by copyright and other intellectual property laws. Any unauthorized use or reproduction is prohibited.

© 2025 Acura Specs. All rights reserved.

Privacy Policy Terms of Service