O&K 4000 Parts Catalog – 180-Page OEM Parts & Operators Manual

Description

I’ve spent over twenty-eight years turning wrenches, and I can tell you right now: the difference between a job that holds up and one that comes back on a hook is the manual you use. This O&K 4000 Parts Catalog is the real deal – factory OEM, printed in 1975, covering serial number 76-4011 and higher. It’s 180 pages of the kind of detail that lets you pull a part number, torque value, or wiring path without guessing. If you’re keeping an O&K 4000 loader in the field, this is the book you want on the bench.

Torque Chart: Page 162

Torque specs are the first thing I check when a fastener comes loose or a joint leaks. Page 162 of this catalog has a full torque chart – bolt sizes, grades, and the ft-lb values that keep the loader from shaking apart. Aftermarket manuals love to leave this out or round numbers. This one gives you the factory spec, not a guess.

Capacities, Pressures, and Electrical System – Page 12

Page 12 is where you find the machine’s vital stats: fluid capacities, system pressures, and electrical system data. That includes battery voltage, alternator output, and starter draw. If you’re troubleshooting a no-start or a hydraulic pressure drop, start here. The manual also dedicates pages 70–73 to battery and wiring for both GM and Cummins diesel versions – critical when you’re swapping a harness or chasing a ground fault.

Adjustments: Pages 15–20

Loader geometry changes over time. The adjustment procedures on pages 15 through 20 cover bucket leveler linkage, steering stops, and brake pedal free play. I’ve seen guys crank on a turnbuckle without the spec and end up with a bucket that won’t dump level. This section gives you the exact clearances and adjustment sequences.

Lubrication Charts and Instructions – Pages 23–31

Lubrication is the cheap insurance on any loader. Pages 23–26 lay out the lubrication instructions, and pages 30–31 have the lubrication charts – what grease, which interval, how many pumps. Ignore these and you’ll be replacing pins and bushings inside a year. The manual even lists the filter and breather replacement schedule on pages 21–23.

3 Systems You Can’t Skip: Filters, Breathers, and Tires

Filters and breathers are covered on pages 21–23. Tires (sizes, pressures, and mounting notes) are on pages 28–29. These sections are short but packed with specs that aftermarket catalogs often omit. If you’re putting new rubber on the 4000, you’ll need the tire data from page 28.

FAQ

Does the manual include wiring diagrams for the electrical system?

Yes, pages 70–73 cover battery and wiring for both GM and Cummins diesel versions.

How do I identify the correct part number for the main hydraulic pump?

You need to cross-reference the machine serial number with the parts listings. The manual includes exploded views and part numbers for the main hydraulic pump on pages 44–45. But note there are two variations depending on whether the loader is equipped with GM or Cummins engine. The manual covers both, but you must check the serial number range (76-4011 & higher) to ensure you get the correct revision. Also, the hydraulic system section on page 76 shows the overall schematic. If you have the wrong pump, you can cause pressure issues. Always verify the part number against the illustration in the catalog.

Related Manuals

• O&K 4000 Technical Manual
• O&K 4000 Parts Catalog – Section: Axle A
• O&K L45, 4500Z 1990 Parts Catalog – Parts Manual TB126

This manual isn’t a reprint or a third-party compilation. It’s the original OEM document that Eaton (Construction Equipment Division) sent out with the machine. For general standards on heavy equipment documentation, see Automotive Industry Overview. Another reference point for similar factory specs is Automotive Industry Overview.

If you’re serious about keeping your O&K 4000 loader running right, access the factory manual. You’ll get the 180-page PDF with the torque chart, electrical data, and every part number you need. No guesswork, just the OEM spec that’s been proven on the job site since 1975.