John Deere 644H, 644H MH Loader Operation and Test Technical Manual TM1637

John Deere operation and test technical manual TM1637 for the 644H wheel loader and the 644H MH (material handler).

This is the diagnostic book. It explains how each system works and how to test it, so you can find the fault before you start pulling parts. The engine is the John Deere 8.1 L.

Compatibility and quick facts

• Make: John Deere
• Models: 644H, 644H MH
• Book code: TM1637
• Engine: John Deere 8.1 L
• Serial notes: Changes marked at serials such as 571786, 574051 and 585561
• Repair book: TM1638 (separate)
• Edition: 15 Jan 2004
• Manual type: Technical manual (operation and tests)
• Language: English
• Length: 392 pages
• Format: PDF, download link right after checkout

What is inside

• Diagnostic trouble codes and how to clear them
• Electrical system theory, schematics and testing
• Engine and fuel system checks
• Transmission operation and pressure tests
• Hydraulic system operation, pressure and flow tests
• Steering and brake tests
• Air conditioning and heating tests

Good to know before you buy

John Deere technical manuals are written for a trained mechanic. Each group starts with the special tools, specs, wear limits and torque values you need, then the steps.

Common questions

Does it have wiring diagrams?
Yes, with system schematics and component location.

Does it cover the MH material handler version?
Yes, the 644H MH is covered in the same book.