Description

O&K 4000 Parts Catalog – What You Get With 272 Pages of Factory Documentation

If you’re tearing into an O&K 4000 loader, you need part numbers that match what came off the line. Not aftermarket redraws, not fuzzy scans of a scan. That file you just obtained from a forum? Often misses a key revision. This Parts Catalog runs 272 pages of OEM breakdowns – axles, brakes, steering cylinders, transmission clutches, you name it. I’ve used these factory docs on job sites from San Antonio to Odessa, and they save the headache of ordering a wheel seal that doesn’t fit because the drawing omitted the spacer.

Everything inside comes straight from Terex (the OEM behind O&K’s North American lineup). Serial number range 40-1011 and higher. That matters because later machines had a different brake valve spring. The manual spells out the exact axle assembly pages – front axle on page 148, rear on 149 – with every bushing, bearing, and shim called out. Want to rebuild the front brake? Pages 152-153 give you the exploded view and part numbers for the brake, axle (front). The rear brake is pages 158-159. Same format, same level of detail.

Axle, Brake, and Drivetrain Coverage – Front and Rear

Axle work is the kind of job where a wrong part number means the machine sits for a week waiting on a replacement. This catalog splits front and rear assemblies clearly. Air chambers, brake controls, lines – every piece is listed. The table of contents shows “Air Chamber, Front Axle – 142, 143” right next to “Air Chamber, Rear Axle – 144.” No guessing whether they’re the same part; you see the diagram and the part number. Same for the “Brake, Axle (Front) – 152, 153” and “Brake, Axle (Rear) – 158, 159.” If you’ve ever had a caliper bracket bolt snap because you used a generic substitute, you understand why the OEM number matters.

Hydraulics, Steering, and Bucket Cylinders

Main hydraulic control valve (2 spool) is covered on pages 86-87. Bucket cylinder pages 88, 89A, 89B. Lift cylinder pages 90-91. Steering cylinder page 104. Each page shows every seal, piston, rod, and fitting. If you’re resealing a bucket cylinder on a 4000, you don’t want to guess the O-ring cross-section – the catalog gives you the Eaton/OEM number. The bucket cylinder piping is page 82. Steering? The cylinder is there, plus the air shift lever (page 95) and the clutch cut-out switch (page 111). A lot of shops skip the clutch cut-out adjustment and then wonder why the forward-reverse shift hangs up. This manual shows the system pages 116-117.

Electrical, Air System, and Transmission Parts

Battery and wiring for GM and CO (Cummins?) powertrains are shown across multiple pages: 74, 75, 75A, 770, 77E, 77F – and the CO variant on 76, 77, 770, 77E, 77F. Air compressor piping for GM on 134-135A, for CO on 136-137A. Air governor page 139A. Transmission case assembly pages 124-125, control valve pages 126-127. Clutch groups – input-reverse/3rd-4th page 129, 1st and 2nd page 128. If you’re rebuilding that transmission, you need the exact bushing and seal part numbers for the clutch packs. Aftermarket catalogs often lump multiple models together and leave you guessing which thrust washer goes where. This one doesn’t.

3 Reasons to Choose OEM Documentation Over Aftermarket

First, the part numbers are the numbers that Eaton/Terex printed. Not someone’s cross-reference that might be off by a digit. Second, the diagrams show the assembly order – you can see whether a snap ring goes inboard or outboard of the bearing. Third, the warranty statement (page 2) tells you the manufacturer’s original coverage terms. When a customer asks why you’re using a certain seal, you can show them the factory page. Aftermarket catalogs skip those details entirely.

This catalog also includes stuff like the automatic bucket leveler (pages 54, 54B, 54C), the ball slip assembly (page 146), belly pans and guards (47A, 47B), and decals (page 83). Not every job is a major overhaul – sometimes you just need the decal for the control pattern or the correct air cylinder (page 94) for the shift system. It’s all in one document.

Does this Parts Catalog cover the O&K 4000 engine and fuel system?

No.

How do I find a specific part number for the rear axle brake?

Look at pages 158-159 for the exploded diagram. Every item is numbered and keyed to a part list in the same spread. The catalog uses OEM Terex/Eaton numbers. If you need the air chamber for the rear axle, that’s page 144. If the brake controls or lines are separate, they’re on pages 132-133. Always check the “Brake Controls and Lines (Front)” page 132 and “Brake Controls and Lines (Rear)” page 133 – sometimes the line kit supersedes a single part. The manual doesn’t leave those ambiguities.

Documents like this are the difference between a repair that holds and a string of “that didn’t fit” phone calls. If you’re working on an O&K 4000, Access the Factory Manual and keep it on the tablet next to the toolbox.

Related manuals that pair with this: O&K 4000 Parts and Operators Manual – Section: Tires, O&K 4000 Technical Manual, O&K L45, 4500Z 1990 Parts Catalog – Parts Manual TB126. For background on why factory specs matter, see the Automotive Industry Overview and Automotive Industry Overview.