TM14078X19 John Deere 670G, 670GP, 672G, 672GP Motor Graders Pdf Repair Service Technical Manual

John Deere 670G, 670GP, 672G, 672GP (SN. C678818—680877) Motor Grader Repair Service Technical Manual (TM14078X19)

For the precise mid-range G-Series graders (specifically Serial Numbers C678818 through 680877), maintaining mechanical integrity is key to staying profitable. The John Deere 670G-672GP Service Repair Technical Manual (TM14078X19) is the dedicated mechanical authority for these machines. Unlike the diagnostic manual, which focuses on sensors and software, this document is strictly for the heavy repair work: disassembly, component inspection, and physical rebuilding. It provides the workshop-level data required to strip a 670G down to the frame and restore it to factory specifications.

When a transmission slips or a front axle seal fails on a 672G, you need accurate, model-specific instructions. TM14078X19 delivers the exact torque values, clearance tolerances, and seal depths for this specific serial number range. Whether you are replacing the circle wear inserts to tighten up a blade or performing a complete differential overhaul, this manual ensures that every bolt is turned correctly and every shim pack is measured to the thousandth of an inch.

TM14078X19 Repair Manual Specifications

• Models Covered: John Deere 670G, 670GP, 672G, 672GP
• Serial Number Range: C678818—680877
• Document Number: TM14078X19
• Document Class: Service Repair Technical Manual (Mechanical)
• Focus: Mechanical Teardown, Rebuild, and Installation
• Key Data: Torque Specs, Wear Limits, and Assembly Sequences
• 6WD Coverage: Front Axle Mechanical Repair (672G/GP)
• Format: Searchable, Printable PDF
• Language: English

Mechanical Rebuild & Service Procedures

Transmission & Differential Internal Repair

The 670G’s PowerShift transmission is a complex assembly of clutches and planetaries. This manual guides you through the complete internal repair of the transmission and differential. It details the safe removal of the unit from the chassis, the disassembly of the clutch packs, and the inspection of gears for pitting or stress. Crucially, it provides the shim adjustment procedures for the differential lock, ensuring that the grader maintains maximum traction without binding during turns.

6WD Front Axle Hub Service (672G/GP)

The 672G’s Six-Wheel Drive system adds a layer of mechanical complexity to the front end. TM14078X19 is essential for servicing the powered front hubs and hydrostatic motors. It covers the removal of the hub assembly, the replacement of the duo-cone face seals, and the critical wheel bearing preload adjustment. Neglecting these tolerances can lead to catastrophic hub failure; this manual gives you the data to do it right.

 

Hydraulic Cylinder & Pump Mechanics

leaks are a common enemy in earthmoving. This manual provides the exploded-view diagrams and procedures for resealing all hydraulic cylinders, including the blade lift, side shift, and articulation cylinders. It specifies the correct tool usage for gland nut removal and piston seal installation. Additionally, it covers the mechanical removal and shaft seal replacement of the main hydraulic pumps, allowing you to refurbish leaking components instead of purchasing expensive new units.

 

Who Needs This Service Manual?

• Heavy Duty Mechanics: Performing engine swaps, transmission rebuilds, and major component repairs.
• Fleet Managers: ensuring that older machines in the C678818—680877 range are maintained to factory standards.
• Hydraulic Shops: Needing specific seal kit diagrams and pump assembly torques.
• Vocational Instructors: Teaching the correct disassembly procedures for heavy construction equipment.

Why Source from Manualsmarket.com?

At Manualsmarket.com, we understand that for specific serial number ranges, generic manuals simply won't cut it. We provide the authentic John Deere 670G/672G Repair Manual (TM14078X19) to ensure you have the exact technical data for your specific machine generation. When you are deep in a teardown, accuracy is the difference between a successful repair and a comeback. Our manuals deliver the uncompromised factory data you need to fix it right the first time.

Visit the John Deere Equipments Collection to complete your technical library with both Repair and Diagnostic manuals.

John Deere 670G-672G Repair FAQ

Does this manual cover electrical troubleshooting?

No. Wiring diagrams, fault codes, and electrical diagnostics are exclusively found in the separate Operation and Test (Diagnostic) Manual. This book covers mechanical repair.

Is the engine repair included?

This manual covers the engine removal and installation from the frame. For the internal rebuilding of the engine block (crankshaft, pistons), you will need the separate Component Technical Manual (CTM).

Does it cover the 6WD system?

Yes. It covers the mechanical disassembly and repair of the 6WD front axle hubs and motor mounting for the 672G and 672GP models.

Are torque specs included for frame bolts?

Yes. A complete torque specification chart for all major fasteners, including circle drive bolts and wheel lugs, is included.