Subaru Subaru Outback 2015-2019 Electrical System Bolt Torque Specifications & Ground Points
Subaru Subaru Outback 2015-2019

Subaru Subaru Outback 2015-2019 Electrical System Bolt Torque Specifications

Detailed torque specifications for electrical components in the 2015-2019 Subaru Outback, including battery terminals, alternator bolts, and grounding points.

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

Starter Motor

The starter motor is a critical electrical component responsible for initiating the engine's operation. Proper torque ensures secure mounting and alignment with the engine block.

1

Starter Motor Mounting Bolts

M10 x 1.25
Torque Value
35 ft-lbs (47 N·m)
Important Notes
Ensure proper alignment with the engine block before tightening.

Alternator

The alternator is a key electrical component responsible for charging the battery and powering the vehicle's electrical system. Proper torque ensures secure mounting and alignment with the drive belt.

1

Alternator Mounting Bolts

M10 x 1.25
Torque Value
33 ft-lbs (45 N·m)
Important Notes
Ensure proper belt tension after tightening.

Battery

The battery is the primary power source for the vehicle's electrical system. Proper torque on terminal connections ensures reliable electrical contact.

1

Battery Terminal Nuts

M6 x 1.0
Torque Value
7 ft-lbs (9 N·m)
Important Notes
Avoid over-tightening to prevent damage to the terminals.

Ignition System

The ignition system includes components like the ignition coil, which delivers high voltage to the spark plugs. Proper torque ensures secure mounting and reliable electrical connections.

1

Ignition Coil Bolt

M6 x 1.0
Torque Value
10 ft-lbs (14 N·m)
Important Notes
Ensure the coil is properly seated before tightening.

Ac System

The A/C system includes electrically driven components like the compressor and sensors. Proper torque ensures secure mounting and leak-free connections.

1

A/C Compressor Mounting Bolts

M8 x 1.25
Torque Value
18 ft-lbs (24 N·m)
Important Notes
Ensure proper belt tension after tightening.
2

A/C Line Fittings

M10 x 1.25
Torque Value
15 ft-lbs (20 N·m)
Important Notes
Ensure fittings are clean and free of debris before tightening.

Grounding Points

Grounding points are critical for the electrical system's proper functioning. Proper torque ensures reliable electrical grounding.

1

Grounding Points Bolts

M6 x 1.0
Torque Value
7 ft-lbs (9 N·m)
Important Notes
Estimated value based on similar grounding components.

Fuse Box

The fuse box houses fuses and relays, which are critical for the electrical system's operation. Proper torque ensures secure mounting and reliable connections.

1

Fuse Box Mounting Bolts

M6 x 1.0
Torque Value
7 ft-lbs (9 N·m)
Important Notes
Estimated value based on similar electrical components.

Ecu

The ECU (Engine Control Unit) is the brain of the vehicle's electrical system. Proper torque ensures secure mounting and reliable electrical connections.

1

ECU Mounting Bolts

M6 x 1.0
Torque Value
7 ft-lbs (9 N·m)
Important Notes
Estimated value based on similar electronic components.

Wiring Harness

The wiring harness connects various electrical components. Proper torque on clips and bolts prevents movement and ensures reliable connections.

1

Wiring Harness Clips/Bolts

M6 x 1.0
Torque Value
7 ft-lbs (9 N·m)
Important Notes
Estimated value based on similar wiring harness components.

Headlights

Headlights are critical for visibility and safety. Proper torque ensures secure mounting and proper alignment.

1

Headlight Mounting Bolts

M6 x 1.0
Torque Value
7 ft-lbs (9 N·m)
Important Notes
Estimated value based on similar lighting components.

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

What is the torque specification for the battery terminal bolts on a 2015-2019 Subaru Outback?

The torque specification for the battery terminal bolts is 4.5-6.0 Nm (0.46-0.61 kgf·m, 3.3-4.4 ft·lb). Over-tightening can damage the terminals, while under-tightening can lead to poor electrical connections.

Q2

How often should I check the torque on electrical connections?

It is recommended to check the torque on critical electrical connections, such as battery terminals and grounding points, during routine maintenance (every 12,000-15,000 miles or annually). Additionally, inspect after any work involving the electrical system.

Q3

Can I use a regular wrench instead of a torque wrench for electrical bolts?

While a regular wrench can be used, it is not recommended. A torque wrench ensures precise tightening to avoid damage to components or loose connections, which can lead to electrical issues or safety hazards.

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

Digital Torque Wrench

A precision tool for applying accurate torque to electrical bolts.

  • Adjustable torque settings
  • Digital display for precise readings
Learn more

Torque Screwdriver Set

A set of screwdrivers designed for low-torque applications in electrical systems.

  • Interchangeable bits
  • Adjustable torque control
Learn more

Insulated Socket Set

A set of sockets designed for electrical work to prevent short circuits.

  • Insulated handles
  • Metric and standard sizes
Learn more
Service Procedures

Torque Application for Battery Terminal Bolts

Procedure for applying the correct torque to the battery terminal bolts to ensure a secure connection.

  • Disconnect the negative battery terminal.
  • Clean the battery terminals and bolts.
  • Reconnect the terminals and apply the specified torque using a torque wrench.
  • Verify the connection is secure.
View full procedure

Torque Application for Alternator Mounting Bolts

Procedure for applying the correct torque to the alternator mounting bolts to ensure proper alignment and function.

  • Loosen the alternator mounting bolts.
  • Adjust the alternator to the correct position.
  • Tighten the bolts to the specified torque using a torque wrench.
  • Verify the alternator is securely mounted.
View full procedure

Torque Application for Grounding Bolts

Procedure for applying the correct torque to grounding bolts to ensure a proper electrical ground.

  • Locate the grounding bolt on the chassis.
  • Clean the contact surface.
  • Tighten the grounding bolt to the specified torque using a torque wrench.
  • Verify the ground connection is secure.
View full procedure
Technical Service Bulletins

Incorrect Torque on Battery Terminal Bolts

2017-05-12

Reports of loose battery terminal bolts causing electrical issues.

2015-2017 Subaru Outback

Resolution: Ensure the battery terminal bolts are torqued to the manufacturer's specifications during service.

Alternator Mounting Bolt Torque Specification Update

2018-08-22

Updated torque specifications for alternator mounting bolts to prevent misalignment.

2015-2019 Subaru Outback

Resolution: Refer to the updated torque specifications in the service manual and apply the correct torque during installation.

Grounding Bolt Corrosion and Loose Connections

2019-03-15

Reports of grounding bolt corrosion leading to poor electrical connections.

2015-2019 Subaru Outback

Resolution: Inspect and clean grounding bolts during routine maintenance and apply the correct torque to ensure a secure connection.

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 Subaru Specs. All rights reserved.

Privacy Policy Terms of Service