Replacing the Blade Pivot Trunnion on a John Deere 450G Dozer

[MikePhua]

       

Introduction
The blade pivot trunnion is a critical component of the John Deere 450G dozer's blade assembly. It facilitates the articulation of the blade, allowing for precise control during operations such as grading and leveling. Over time, wear and tear can compromise its integrity, leading to potential issues like excessive play, misalignment, or even failure. Addressing these concerns promptly is essential to maintain optimal performance and safety.
Understanding the Blade Pivot Trunnion Assembly
The blade pivot trunnion assembly comprises several key components:

• Trunnion Ball (Part # T147801): This spherical component serves as the central pivot point for the blade.
  
• Socket with Gussets (Part # T180534): Houses the trunnion ball and provides structural support.
  
• Socket Cap (Part # T180535): Secures the trunnion ball within the socket.
  
• Mounting Bolts (Part # 19M7963): Fasten the assembly to the dozer's frame.
  

These parts are available individually or as a complete kit, often referred to as the T147801-KIT. Aftermarket options are also available, such as the RAParts assembly, which includes all necessary components for replacement.
Symptoms of a Worn or Damaged Blade Pivot Trunnion
Operators may notice several signs indicating issues with the blade pivot trunnion:

• Excessive Blade Play: Noticeable movement or wobbling of the blade during operation.
  
• Misalignment: The blade may not return to its neutral position after adjustments.
  
• Unusual Noises: Grinding or clunking sounds when the blade is moved.
  
• Uneven Wear Patterns: Irregularities on the blade or surrounding components.
  

If these symptoms are observed, it's advisable to inspect the blade pivot trunnion for wear or damage.
Replacement Procedure

1. Preparation:
   • Park the dozer on a level surface and engage the parking brake.
     
   • Raise the blade and secure it using appropriate supports.
     
2. Removal:
   • Locate and remove the mounting bolts (Part # 19M7963) securing the blade pivot assembly.
     
   • Carefully detach the socket cap (Part # T180535) and remove the trunnion ball (Part # T147801).
     
   • Take note of any shims or spacers used during assembly for reinstallation.
     
3. Inspection:
   • Examine the socket with gussets (Part # T180534) for signs of wear or damage.
     
   • Check the surrounding components for any issues that may have contributed to the trunnion's failure.
     
4. Installation:
   • Place the new trunnion ball (Part # T147801) into the socket with gussets (Part # T180534).
     
   • Reinstall the socket cap (Part # T180535) and secure it with the mounting bolts (Part # 19M7963).
     
   • Ensure all components are properly aligned and tightened to the manufacturer's specifications.
     
5. Testing:
   • Lower the blade and test its movement to ensure smooth operation.
     
   • Check for any unusual noises or resistance during blade articulation.
     

Maintenance Tips

• Regular Inspections: Periodically check the blade pivot trunnion for signs of wear or damage.
  
• Lubrication: Apply appropriate grease to the trunnion assembly to reduce friction and wear.
  
• Prompt Repairs: Address any issues with the blade pivot trunnion promptly to prevent further damage to the dozer's blade assembly.
  

Conclusion
The blade pivot trunnion is a vital component in the John Deere 450G dozer's blade assembly. Regular maintenance and timely replacement of worn or damaged parts ensure the dozer operates efficiently and safely. By following the outlined procedures and utilizing quality replacement parts, operators can maintain the performance and longevity of their equipment.

For a visual guide on replacing the blade center joint on a John Deere 450G dozer, you can refer to the following video: