KYB MAG-18VP-230F-3 RB511-61290 final drive for Kubota U25S U25-3 U25-3a U25-3S mini excavator
If you decide to buy equipment at a low price, make sure that you communicate with the real seller. Find out as much information about the owner of the equipment as possible. One way of cheating is to represent yourself as a real company. In case of suspicion, inform us about this for additional control, through the feedback form.
Before you decide to make a purchase, carefully review several sales offers to understand the average cost of your chosen equipment. If the price of the offer you like is much lower than similar offers, think about it. A significant price difference may indicate hidden defects or an attempt by the seller to commit fraudulent acts.
Do not buy products which price is too different from the average price for similar equipment.
Do not give consent to dubious pledges and prepaid goods. In case of doubt, do not be afraid to clarify details, ask for additional photographs and documents for equipment, check the authenticity of documents, ask questions.
The most common type of fraud. Unfair sellers may request a certain amount of advance payment to “book” your right to purchase equipment. Thus, fraudsters can collect a large amount and disappear, no longer get in touch.
- Transfer of prepayment to the card
- Do not make an advance payment without paperwork confirming the process of transferring money, if during the communication the seller is in doubt.
- Transfer to the “Trustee” account
- Such a request should be alarming, most likely you are communicating with a fraudster.
- Transfer to a company account with a similar name
- Be careful, fraudsters may disguise themselves as well-known companies, making minor changes to the name. Do not transfer funds if the company name is in doubt.
- Substitution of own details in the invoice of a real company
- Before making a transfer, make sure that the specified details are correct, and whether they relate to the specified company.
Seller's contacts
+86 199 246...
+86 199 2461 6345
China
China
China
China
China
China
China
Romania
Romania
Denmark, Horsens
Denmark, Horsens
Denmark, Horsens
Romania
Romania
Component: Complete Final Drive Assembly (Hydraulic Travel Motor with Planetary Gearbox Reducer)
Hydraulic Motor Model: KYB MAG-18VP-230F-3 (Kayaba MAG Series Architecture)
Kubota OEM Part Numbers: RB511-61290, RB559-61290, RG248-61290, RB511-78000 (RB51161290, RB55961290, RG24861290, RB51178000)
Machine Compatibility:
Kubota U25
Kubota U25S / U25-3S
Kubota U25-3 / U25-3a
Condition: Brand New Original / Premium OEM Specification Equivalent
2. Technical Specifications
Motor Type: Two-Speed Swash Plate Axial Piston Motor
Reducer Type: Compact Heavy-Duty Multi-Stage Planetary Gearbox
Operating Parameters: Factory-calibrated flow rate, displacement, and pressure output matching Kubota 2.5-ton class zero-tail-swing travel circuits.
Integrated Controls: Features automatic two-speed shifting capability, dual main relief valves, counter-balance valves, and internal dynamic parking brakes.
Interface Mounting: 9-bolt or standard flange configuration designed to bolt directly onto the track frame chassis and accept original drive sprockets.
3. Critical Installation Requirements
Travel Motor Housing Priming (Mandatory)
Before running the excavator or driving the tracks, you must manually pre-fill the axial piston motor housing with clean hydraulic fluid through its highest case drain port. Running an axial piston motor bone-dry—even for a few track revolutions—will score the swash plate and piston slippers, causing instant pressure failure.
Verify Case Drain Line Pressure
Inspect the travel motor case drain line back to the hydraulic reservoir. Ensure there are no kinks, restrictions, or line collapses. High backpressure in the travel case drain line will immediately blow out the main hub oil seal and mix hydraulic fluid with gear oil in the gearbox.
Planetary Gearbox Lube Check
Ensure the gear reducer casing is filled to the designated level plug with high-grade gear oil (typically SAE 80W-90 or SAE 90) prior to operation. Drain and replace the break-in gear oil after the first 50 to 100 operating hours.
Hydraulic System Flushing
If replacing a failed final drive that generated internal metal shavings, flush the travel circuit lines, clean out the hydraulic tank, and replace return and pilot oil filters to prevent abrasive wear on the new motor components.
4. Frequently Asked Questions (FAQ)
Q: Are part numbers RB511-61290, RB559-61290, RG248-61290, and RB511-78000 fully interchangeable?
A: Yes. These part numbers reflect standard Kubota engineering updates, dash-model revisions (such as U25-3 vs. U25-3a), and kit configurations across the 2.5-ton mini excavator series. All utilize the core KYB MAG-18VP-230F-3 final drive platform with identical bolt patterns and sprocket fitments.
Q: My excavator tracks slowly or loses pushing power on one side. Is this a final drive issue?
A: Loss of tracking power or slow speed on one side can be caused by worn axial pistons inside the travel motor, internal gear wear in the reducer, or a worn swivel joint (center joint) seal. If hydraulic pressure testing at the motor ports shows proper input pressure but weak output torque, replacing the final drive assembly will resolve the issue.
Q: Does the unit come complete with both the hydraulic motor and gear reducer?
A: Yes. The KYB MAG-18VP-230F-3 assembly is supplied complete, fully integrated with the lower planetary gear reducer, upper axial piston motor, shift valve block, and main brake assembly.
5. Shipping & Logistics
Packaging: Treated with rust-inhibiting anti-corrosion oil, fitted with plastic port plugs, and secured inside an export-safe protective crate or reinforced box.
Transit Time: Global express air freight via DHL/FedEx/UPS typically delivers within 3 to 7 business days directly to your shop or job site.