The Wacker Neuson Piston Complete is a genuine OEM component designed for the APT4S and APT4T pump series, including standard, surge brake, electric brake, and cold weather configurations. As a direct OEM part, the is manufactured to the same specifications as the original, ensuring a proper fit within the pump assembly without guesswork or rework. This piston complete covers a broad range of APT4 variants — including the APT4S Pump with Skid, APT4T Pump with Surge Brake, APT4T Pump with Electric Brake, and their respective cold weather counterparts — making it a versatile service part for fleets running multiple APT4 configurations. When it's time to restore pump performance, sourcing the correct OEM piston assembly means the repair is done right the first time.
Key Features
- OEM-Spec Piston Tolerancing — Manufactured to exacting dimensional tolerances to maintain proper compression and seal contact within the pump cylinder bore.
- Drop-In Assembly Fit — Supplied as a complete piston assembly, so installation follows the original service procedure with no additional machining or adaptation.
- Broad APT4 Series Coverage — Fits APT4S and APT4T pump models across standard and cold weather variants, including surge brake and electric brake configurations.
- Sustained Pump Output — A correctly fitted piston complete maintains consistent pressure and flow, keeping the pump performing at rated capacity over extended service cycles.
- Genuine Wacker Neuson Part — Sourced directly from Wacker Neuson, part number 5200020044 carries the same quality assurance as the component it was built to replace.
The piston is the reciprocating heart of a hydraulic or fluid pump — it draws fluid in on the intake stroke and forces it out under pressure on the compression stroke. In an APT4 pump, a worn or damaged piston results in loss of pressure, reduced flow output, and increased internal leakage that causes the pump to work harder and overheat. Replacing the piston complete as an assembly restores the designed compression ratio and seal geometry, returning the pump to full operational efficiency.
Part Details
| Part Number | 5200020044 |
|---|---|
| Brand | Wacker Neuson |
| Part Type | Genuine OEM |
| Description | Piston Complete |
Compatibility & Fitment
| Name | Model | Machine Number |
|---|---|---|
| APT4S Pump w/Skid | APT4S | 5200018977 |
| APT4T Pump, Surge Brake | APT4T | 5200019643, 5200019644 |
| APT4T Pump, Surge Brake, Cold Weather | APT4T CW | 5200019792, 5200019793 |
| APT4S Pump w/Skid, Cold Weather | APT4S CW | 5200019798 |
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.
