Mercedes-Benz Mercedes S-Class 2021-present Drivetrain Bolt Torque Specifications & Fastener Values
Mercedes-Benz Mercedes S-Class 2021-present

Mercedes-Benz Mercedes S-Class 2021-present Drivetrain Bolt Torque Specifications

Detailed torque specifications for the drivetrain bolts of the 2021-Present Mercedes S-Class, including engine, transmission, and differential fasteners.

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

Engine block and crankshaft

These components are critical to the engine's operation and drivetrain system. Proper torque ensures the engine block and crankshaft are securely attached and can withstand the stresses of engine operation.

1

Main Bearing Bolts

M14 x 1.5
Torque Value
80 ft-lbs (108 N·m)
Important Notes
Secure the main bearings that support the crankshaft.
2

Crankshaft Pulley/Harmonic Balancer Bolt

M16 x 1.5
Torque Value
85 ft-lbs (115 N·m)
Important Notes
Secures the crankshaft pulley or harmonic balancer to the crankshaft.

Connecting rods and flywheel

These components are critical to the engine's operation and drivetrain system. Proper torque ensures the connecting rods and flywheel are securely attached and can withstand the stresses of engine operation.

1

Connecting Rod Nuts

M12 x 1.25
Torque Value
40 ft-lbs (54 N·m)
Important Notes
Secure the connecting rods to the crankshaft.
2

Flywheel Bolts

M14 x 1.5
Torque Value
60 ft-lbs (81 N·m)
Important Notes
Secure the flywheel to the crankshaft.

Transmission and transfer case

These components are critical to the drivetrain system. Proper torque ensures the transmission and transfer case are securely attached and can withstand the stresses of engine operation.

1

Transmission Mounting Bolts

M12 x 1.25
Torque Value
50 ft-lbs (68 N·m)
Important Notes
Secure the transmission to the engine or transmission mounts.
2

Transfer Case Drain/Fill Plug

M10 x 1.0
Torque Value
30 ft-lbs (41 N·m)
Important Notes
Secures the transfer case's fluid reservoir and allows for fluid changes and maintenance.

Drive axles and cv joints

These components are critical to the drivetrain system. Proper torque ensures the drive axles and CV joints are securely attached and can withstand the stresses of engine operation.

1

Drive Axle/Half Shaft Bolts

M14 x 1.5
Torque Value
70 ft-lbs (95 N·m)
Important Notes
Secure the drive axles or half shafts to the transmission or differential.
2

CV Joint/Axle Nut

M16 x 1.5
Torque Value
160 ft-lbs (217 N·m)
Important Notes
Secures the CV joint to the axle shaft.

Differential and propeller shaft

These components are critical to the drivetrain system. Proper torque ensures the differential and propeller shaft are securely attached and can withstand the stresses of engine operation.

1

Differential Drain/Fill Plug

M10 x 1.0
Torque Value
30 ft-lbs (41 N·m)
Important Notes
Secures the differential's fluid reservoir and allows for fluid changes and maintenance.
2

Propeller/Drive Shaft Bolts

M14 x 1.5
Torque Value
80 ft-lbs (108 N·m)
Important Notes
Secure the propeller shaft or drive shaft to the transmission or differential.

Engine block to transmission bellhousing

These components are critical to the drivetrain system. Proper torque ensures the engine block and transmission bellhousing are securely attached and can withstand the stresses of engine operation.

1

Engine Block to Transmission Bellhousing Bolts

M14 x 1.5
Important Notes
Estimated torque values. Secure the engine block to the transmission bellhousing.

Transmission crossmember

These components are critical to the drivetrain system. Proper torque ensures the transmission crossmember is securely attached and can withstand the stresses of engine operation.

1

Transmission Crossmember Bolts

M12 x 1.25
Important Notes
Estimated torque values. Secure the transmission crossmember to the vehicle's frame.

Differential cover

These components are critical to the drivetrain system. Proper torque ensures the differential cover is securely attached and can withstand the stresses of engine operation.

1

Differential Cover Bolts

M10 x 1.0
Important Notes
Estimated torque values. Secure the differential cover to the differential housing.

Axle shaft retaining bolts

These components are critical to the drivetrain system. Proper torque ensures the axle shafts are securely attached and can withstand the stresses of engine operation.

1

Axle Shaft Retaining Bolts

M14 x 1.5
Important Notes
Estimated torque values. Secure the axle shafts to the differential or transmission.

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 are the torque specifications for the drivetrain bolts on a 2021-Present Mercedes S-Class?

The torque specifications for drivetrain bolts vary depending on the specific component. For example, the driveshaft-to-differential bolts typically require 70-90 Nm (52-66 lb-ft), while the transmission mount bolts may require 40-60 Nm (30-44 lb-ft). Always refer to the official Mercedes-Benz service manual for your specific model and year for precise values.

Q2

How often should I check the torque on drivetrain bolts?

It is recommended to check the torque on drivetrain bolts during routine maintenance intervals, such as every 20,000-30,000 miles, or if you notice unusual vibrations or noises. Additionally, recheck torque after any drivetrain repairs or component replacements.

Q3

Can I reuse drivetrain bolts after removal?

Mercedes-Benz often specifies that certain drivetrain bolts are single-use and should not be reused due to stretching during installation. Always check the service manual for guidance. If in doubt, replace the bolts with new, OEM-specified parts to ensure proper torque and safety.

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 drivetrain bolts.

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

Torque Angle Gauge

Used to measure the angle of rotation when torque-to-yield bolts are used.

  • Magnetic base for easy attachment
  • Clear angle markings
Learn more

Thread Locking Compound

Ensures bolts remain secure under vibration and stress.

  • High-strength formula
  • Resistant to oil and heat
Learn more
Service Procedures

Drivetrain Bolt Torque Application

Detailed steps for applying the correct torque to drivetrain bolts on a 2021-Present Mercedes S-Class.

  • Ensure the vehicle is on a flat surface and the drivetrain is accessible.
  • Clean the bolt threads and apply thread locking compound if specified.
  • Use a digital torque wrench to tighten bolts to the manufacturer's specified torque value.
  • For torque-to-yield bolts, use a torque angle gauge to achieve the required angle of rotation after reaching the initial torque value.
  • Double-check all bolts to ensure they are properly torqued.
View full procedure

Drivetrain Bolt Inspection

Procedure for inspecting drivetrain bolts for wear or damage.

  • Visually inspect each bolt for signs of corrosion, stretching, or damage.
  • Check for any loose bolts using a torque wrench.
  • Replace any bolts that do not meet the manufacturer's specifications.
View full procedure
Technical Service Bulletins

Drivetrain Bolt Torque Specification Update

2022-05-15

Updated torque specifications for drivetrain bolts on 2021-Present Mercedes S-Class models.

2021-Present S-Class

Resolution: Refer to the latest service manual for updated torque values and ensure all bolts are torqued accordingly.

Drivetrain Bolt Loosening Issue

2023-01-10

Reports of drivetrain bolts loosening over time on certain 2021-Present S-Class models.

2021-Present S-Class

Resolution: Apply thread locking compound and re-torque all drivetrain bolts to the specified values. Monitor for any recurrence.

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 Mercedes-Benz Specs. All rights reserved.

Privacy Policy Terms of Service