Description

Kubota RW-25, RW-25S Technical Manual

You are fighting a Kubota RW-25 that won’t pull uphill like it used to. Aftermarket website tells you to check the clutch, but doesn’t give you the inertia brake clearance or the transmission case bearing numbers. That’s the difference between a job done right and a machine that comes back on a hook.

This Kubota RW-25, RW-25S Technical Manual is not a chiltons. It’s 16 pages of factory test procedures straight from Kubota. No filler, no advertising. You get the power transmission flow chart (page 1) that shows exactly how torque flows from the engine through the universal joints, differential cases, and main brakes. Need to know the bearing part numbers? The flow chart lists 30212, 73889, N22209, and needle bearing PK30x40x19.8. That’s information you use to order parts before you pull the axle.

Power Transmission Flow Chart and Clutch Specs

Page 1 lays out the entire driveline in a single diagram. Engine connects to a clutch, then to a transmission case, then through universal joints to front and rear differential cases. The inertia brake sits on the transmission case. Both front and rear axles use bilateral symmetry — same bearings on each side. If you are rebuilding a transmission in a RW-25S, you need to see this chart. It shows the gear count (27T on one shaft) and the exact bearing locations. Manual Transmission fundamentals apply, but Kubota uses their own internal layout. Don’t guess which bearing goes where.

17 Performance Tests – What to Check and How

The manual lists seventeen specific tests, each with a measurement method and acceptance criteria. Here is the lineup:

• Measurement of main dimensions (page 2) – overall length, width, wheelbase, tread, ground clearance, dumping clearance and reach. All in inches and degrees.
• Measurement of weight and gravitational center (page 3)
• Measurement of overturn load (page 4)
• Measurement of bucket capacity (page 4)
• Travelling speed test (page 5)
• Measurement of turning radius (page 5)
• Travelling resistance test (page 6)
• Ascending performance test (page 6)
• Brake performance test (page 7) – critical for safety certification.
• Measurement of maximum traction (page 8)
• Shovel loading performance test (page 8)
• Channel digging performance test (page 9)
• Levelling efficiency test (page 10)
• Operating force test (page 11)
• Operation power test (page 11)
• Control power and range test (page 12)
• Measurement of visibility at operator’s seat (page 13)

Tire pressure is specified on page 2: 28.4 psi front and rear, left and right. That is 0.2 MPa. If you are setting up a RW-25 after a tire swap, that number is in the manual. Don’t rely on a sidewall max rating.

Who Actually Needs This 16-Page Manual?

Two types of people: a home garage owner who bought a used RW-25S and wants to verify it still meets factory specs, and a small equipment shop that does rental fleet maintenance. If you are the first guy, you can use the dimensional checks to confirm your machine hasn’t been bent by a previous operator. If you are the shop guy, the brake performance test and ascending performance test are your go-to for passing safety inspections. Related manuals for other Kubota models include Kubota STV32 STV36 STV40 2006 Technical Manual – Flat Rate Schedule for flat rate times, and Kubota RTV900G, RTV900W, RTV900R, RTV900W EC, RTV900 EC 2006 Technical Manual for utility vehicle specs. For a compact tractor family, see Kubota B21, B2320, B2620, B2920 Technical Manual – 292-Page Factory Service Manu.

Why OEM Documentation Beats Aftermarket Copies

Aftermarket manuals reprint the same drawings but often change the torque values or omit the step where you measure the gravitational center before the overturn load test. Kubota’s engineering department wrote this document for their own technicians. The page numbers are consistent, the tolerances are original. For example, the measurement of main dimensions on page 2 gives exact inches: 141.7 in. overall length, 65.9 in. overall width, 63.0 in. wheelbase. Those are the numbers you use to confirm the frame is straight. No guessing.

Does This Manual Cover the Fuel System or Engine Overhaul?

No. This is a performance test manual, not a service repair manual. It focuses on dimensional checks, weight, traction, digging, and braking. For engine internal specs, you need the separate engine manual. But if you are verifying the machine’s capabilities after a repair, this is the document.

Why Only 16 Pages – Is That Enough?

Yes. Kubota condensed the essential factory acceptance tests into a compact reference. You can carry it in a binder. Every page is packed with data tables, diagrams, and procedures. The power transmission flow chart alone saves you an hour of tracing lines under the machine. Manual Transmission knowledge helps, but the Kubota-specific bearing numbers and gear counts are here.

Get the Right Specs – Access the Factory Manual

Stop chasing bad data from forum posts. Buy the OEM document, print page 7 for the brake test criteria, and keep it in your toolbox. Access the Factory Manual now and have the exact same information Kubota technicians use.

Does this manual include torque values for the transmission?

No. The manual contains performance test procedures, not torque specifications. Use it to verify machine operation.

How many pages is the manual, and what format does it come in?

16 pages in PDF format. Includes 17 test procedures, a power transmission flow chart, and dimensional data in imperial units. The file works on any device.