Bomag 05542287 Reducing Union

The Bomag 05542287 Reducing Union is a genuine OEM hydraulic fitting designed for a broad range of Bomag compaction and milling equipment, including tandem rollers such as the BW 120 AD-5 and BW 174 AP-4, single drum rollers including the BW 213 DH-5 and BW 177 DH-4, cold milling machines such as the BM 1000/35 and BM 2500/75, refuse and landfill compactors across the BC-series, recyclers and stabilizers including the MPH 122 and RS 500, and pneumatic tyred rollers including the BW 12 R and BW 28 RH. As a genuine OEM component, part number 05542287 is produced to Bomag's exact material and dimensional standards, ensuring a correct, leak-free connection within the hydraulic circuit. This reducing union ships as a direct drop-in replacement, making it a straightforward service part for scheduled maintenance or unplanned repair across a wide fleet.

Key Features

• OEM Hydraulic Sealing Integrity — manufactured to Bomag's exact thread form and bore-reduction specification, delivering a leak-free hydraulic connection without rework or shimming
• Direct Drop-In Replacement — threads and port sizing match the original installed fitting, allowing straightforward installation without machining or adapters
• Broad Fleet Coverage — fits a wide range of Bomag tandem rollers, single drum rollers, cold milling machines, refuse and landfill compactors, soil compactors, recyclers and stabilizers, and pneumatic tyred rollers, including models such as the BW 161 AD-5, BW 213 DH-5, BM 2000/75, BC 772 RB-4, MPH 600, and RS 650, among many others
• Sustained Hydraulic System Pressure — a correctly seated reducing union maintains proper flow and pressure balance between hydraulic lines; a worn or leaking fitting causes pressure loss, overheating, and erratic system response
• Genuine Bomag Part — sourced directly from Bomag's OEM supply chain under part number 05542287, ensuring material grade and thread tolerance match the original equipment specification

A reducing union is a hydraulic fitting used to connect two fluid lines of different diameters within a machine's hydraulic circuit, stepping down from a larger bore to a smaller one while maintaining a sealed, pressure-rated flow path. In Bomag equipment, this type of fitting is typically found where hydraulic supply or return lines transition between components such as pumps, control valves, and actuators. When the union leaks, cracks, or loses thread integrity, the hydraulic circuit loses pressure, fluid contamination risk increases, and the affected system — whether a vibratory drive, steering circuit, or cutting drum — will respond sluggishly or fail to operate altogether. Replacing a damaged reducing union promptly restores circuit integrity and protects downstream hydraulic components from the effects of pressure drop and fluid loss.

Part Details

Compatibility & Fitment

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.