GEHL 860, 865 Parts Catalog

If you are rebuilding a GEHL 860 or 865 forage harvester, you need the real factory parts breakdown—not some aftermarket scanned mess that skips pages and blows up your part numbers. This GEHL 860, 865 Parts Catalog is the exact same 88-page document the dealer pulls up when you call with a serial number. No generic diagrams, no reprints. Page 2 tells you exactly where to find the model and serial number plate (right side of main frame near the Cylinder shaft bearing). You need that number before you order anything, or you will get the wrong drive sprocket and waste a week.

Decal Locations and Frame Assembly

Pages 2-9 cover every decal location—safety, operation, and warning labels—so you can replace missing or faded ones. The Frame & Attachment Lift section (pages 10-11) shows the structural weldments and lift brackets. Working on a machine that has had a bent frame? This is how you check the original geometry. I have seen guys try to straighten a loader frame without a factory drawing; it never comes out right.

Cylinder & Cutting Mechanism – 4 Pages of Specs

The cutting cylinder is the heart of a forage harvester. Pages 14-17 cover the Cylinder blades, knife sharpener, and shear bar. If you are replacing the cylinder assembly, you need the part numbers for the bearing housings, knife clips, and adjustment hardware. The exploded view makes cross-referencing with your old parts straightforward. Do not use generic bolts on the cylinder—they fatigue differently.

Transmission Controls: Standard vs. Metal Detector

Pages 24-27 separate the shifter transmission controls for standard machines and those with the metal detector option. The Electric Clutch for metal detector models is on pages 28-29. Transmission parts are not interchangeable between the two, so verify which harness you have. On page 30-31 you get the upper feed roll drive; lower rollers split by standard and metal detector on pages 32-35. Skip this distinction and you will order a feed roll shaft that does not fit.

Does This Catalog Cover the Hydraulics?

Yes. Pages 48-49 show the main hydraulic system—pump, valves, and hose routing. Hydraulic Components on page 62 adds detail for the cylinders and fittings. There is also a Hydraulic Hitch Control section on page 69 if your machine has that option. The torque values for hydraulic fittings are on the inside back cover; always use the factory spec to avoid blowing a seal at full pressure.

Torque Specs Inside Back Cover – Don’t Guess

The last page of the catalog lists standard hardware torque specifications for Grade 5 bolts and Grade B nuts. That is the only torque table you should trust for this machine. Aftermarket manuals often swap in generic foot-pound values that are too high for the aluminum housings on some older GEHL units. Use what GEHL published.

3 Reasons to Choose OEM Documentation

First, the part numbers in this catalog are the ones GEHL still stocks. Second, the exploded views include tear-drop symbols for wet (oiled) fasteners and hexagon symbols where a specific torque is required. Third, the numerical index on pages 77-84 lets you look up any part number in seconds. I have had to use that index more times than I can count when a customer brings in a bag of bolts and asks, “Where does this go?”

If you are working on a GEHL SL4640, SL4840, SL5640, SL6640 2005 Parts Catalog GEHL SL4640, SL4840, SL5640, SL6640 2005 Parts Catalog or a newer machine like the SL7610, SL7710, SL7810 2005 Parts Catalog – OEM Factory Specs GEHL SL7610, SL7710, SL7810 2005 Parts Catalog – OEM Factory Specs, the same attention to detail applies. For compact loaders, the GEHL RS6-34 2013 Parts Catalog – Factory OEM Manual GEHL RS6-34 2013 Parts Catalog – Factory OEM Manual is another reference you will want on the shelf.

Need a deeper understanding of how the engine interacts with the PTO drive? Check this Wikipedia article on diesel engines for the fundamentals. For technical background on the diesel cycle, this Wikipedia article on diesel engines covers combustion details that help you diagnose low-power issues.

Can I use this catalog to order parts for my GEHL 865 if the serial number plate is missing?

Not directly. GEHL changed design details after serial number 9300. Without the serial number, you risk ordering incorrect Cylinder parts or Transmission sprockets. Use the Frame & Attachment Lift diagram on page 10 to identify key casting numbers, then cross-reference with the numerical index.

Does the inside back cover include metric torque values?

No. All fasteners in this catalog are SAE Grade 5 or Grade B. Metric torque specs are not provided.

You have the serial number. You have the worn-out parts. Now get the exact replacements without second-guessing. Download the Factory Manual and keep a copy in the shop file.