John Deere 670D 870D and 872D Motor Grader Repair Technical Manual
All cover: John Deere 670D, 672D, 770D, 772D, 870D and 872D Motor Grader Repair Technical Manual (TM2256)
Catalog Manual: John D Motor Grader 670d 672d Parts Manual
✅ Engine Systems and Performance Diagnostics
This section explains diesel engine operation, fuel system calibration, air intake evaluation, cooling system efficiency, lubrication pressure checks, and engine performance testing. Procedures focus on mechanical inspection, fault isolation, and confirming proper engine output under grading loads.
✅ Transmission and Powertrain Testing
Covers PowerShift transmission operation, torque converter analysis, driveline inspection, axle function, and differential performance. Diagnostic methods address slippage, overheating, abnormal noise, and loss of tractive effort.
✅ Hydraulic System Operation and Testing
Details hydraulic pump performance testing, control valve function, steering and blade circuit analysis, pressure verification, and cylinder leakage diagnosis to resolve slow response or weak hydraulic functions.
John Deere 670D 870D and 872D Motor Grader Repair Technical Manual
✅ Electrical and Electronic Control Diagnostics
Includes wiring schematic interpretation, sensor signal testing, electronic control modules, starting and charging systems, and diagnostic fault analysis using approved test procedures.
✅ Brake, Steering, and Chassis Systems
Addresses service brake testing, articulation and steering inspection, frame alignment checks, and operational safety verification.
✅ Technical Specifications and Diagnostic Reference Data
Provides system specifications, pressure values, fluid capacities, temperature limits, maintenance intervals, and structured troubleshooting guidance for accurate repair decisions.