The Multiquip 21159 Fitting 45 4MJ-4MO is a genuine OEM hydraulic fitting designed for the HTX44, STX55, STXD6i, and HTXD6i series hydrostatic ride-on power trowels. As a factory-sourced component, it meets the exact specifications of the original part it replaces, ensuring a secure, leak-free connection in the hydraulic system. Verified fitment spans the HTX44K4, HTX44K5, HTX44Y4, HTX44Y5, STX55J6, STX55Y6, STXD6i, and HTXD6i models. When you need to restore hydraulic integrity on your Whiteman ride-on trowel, part number 21159 is the correct OEM choice.
Key Features
- Genuine OEM Hydraulic Integrity — Factory-sourced fitting maintains the pressure rating and thread specification required by the original hydraulic circuit design.
- 45-Degree Male JIC to Male ORB Configuration — The 4MJ-4MO geometry allows the hydraulic line to route at a 45-degree angle, enabling clean, space-efficient plumbing in tight trowel hydraulic assemblies.
- Direct-Fit for HTX44 and STX55 Series — Confirmed OEM fitment for HTX44K4, HTX44K5, HTX44Y4, HTX44Y5, STX55J6, STX55Y6, STXD6i, and HTXD6i hydrostatic ride-on trowels.
- Leak-Free Hydraulic Performance — A correctly seated hydraulic fitting holds system pressure and prevents fluid loss that would otherwise cause inconsistent blade pitch control or drive response.
- Hydraulic System Safety — A failed or improperly rated fitting in a hydrostatic trowel circuit can cause sudden loss of blade or drive control; using the correct OEM part preserves safe, predictable machine operation.
A hydraulic fitting is a threaded connector that joins sections of hydraulic hose or tubing within the machine's fluid circuit. In a hydrostatic ride-on trowel, the hydraulic system controls both blade pitch adjustment and machine drive, so every fitting in the circuit must maintain a sealed, pressure-rated connection. A worn, cracked, or wrong-specification fitting allows hydraulic fluid to leak, which drops system pressure and leads to sluggish or uncontrolled blade response. Replacing a damaged fitting promptly with the correct OEM part restores full hydraulic pressure and keeps the trowel operating predictably across a finish pass.
DHS Equipment is an authorized Multiquip parts dealer. If you need help confirming fitment for your specific machine serial number or have questions about part 21159, contact our parts team directly.
Part Details
| Part Number | 21159 |
|---|---|
| Brand | Multiquip |
| Part Type | Genuine OEM |
| Description | Fitting 45 4MJ-4MO |
Compatibility & Fitment
| Name | Model |
|---|---|
| Whiteman Ride-On Power Trowels | HTX44K4 |
| Whiteman Ride-On Power Trowels | HTX44K5 |
| Whiteman Ride-On Power Trowels | STX55J6 |
| Whiteman Ride-On Power Trowels | HTX44Y4 |
| Whiteman Ride-On Power Trowels | HTX44Y5 |
| Whiteman Ride-On Power Trowels | STXD6i |
| Whiteman Ride-On Power Trowels | HTXD6i |
| Whiteman Ride-On Power Trowels | STX55Y6 |
Verify Before You Order
Fitment is machine-number and revision-specific; always confirm your model and serial number against the fitment list.
Why Buy From DHS Equipment
Every part is verified against the manufacturer's part number before it ships, so what you order is what arrives. We carry parts from leading OEM brands and our own DHS Quality Parts line of professional aftermarket components. Need help finding the right part? Our team is available to confirm compatibility whenever you need it. Orders are processed fast to keep your jobs on track. We don't just sell parts. We keep you jobsite ready.
Questions? Contact our team at [email protected] or 866-611-9369 — DHS Equipment is here to help you maintain peak performance.
