The Wacker Neuson 5200020178 is a genuine OEM O-Ring designed for the APT4S and APT4T series pumps. As a direct OEM replacement, this seal is sourced to the same specifications as the original component installed at the factory, ensuring a proper fit within the pump assembly. Compatible with multiple configurations including cold weather, surge brake, and electric brake variants across the APT4S and APT4T pump families, this O-Ring covers a broad range of units in the field. Keep a spare on hand to minimize seal-related service delays during critical operations.
Key Features
- OEM Seal Integrity — Manufactured to the same material and compression tolerances as the original, maintaining the fluid-tight seal the pump system depends on.
- Drop-In Installation — Sized to seat correctly in the existing groove without trimming or adjustment, making replacement straightforward during scheduled service or field repair.
- Broad APT4S and APT4T Coverage — Fits cold weather, surge brake, and electric brake configurations across both pump model families, so one part number serves multiple units.
- Prevents Fluid Loss and Contamination — A worn or cracked O-Ring allows fluid to bypass the seal, leading to leaks, pressure loss, and potential pump damage if left unaddressed.
- Fluid System Safety — Maintaining a sound seal is essential in pump systems to prevent uncontrolled fluid discharge and protect downstream components from contamination or pressure fluctuation.
An O-Ring is a precision loop seal used at connection points within a pump assembly to prevent fluid from escaping between mating surfaces. In the APT4S and APT4T pump systems, O-Rings maintain pressure integrity and keep fluid contained as it moves through the system. When an O-Ring degrades — due to heat cycling, chemical exposure, or compression set — it loses its ability to seal properly, resulting in leaks, reduced pump efficiency, and potential damage to surrounding components.
Part Details
| Part Number | 5200020178 |
|---|---|
| Brand | Wacker Neuson |
| Part Type | Genuine OEM |
| Description | O-Ring |
Compatibility & Fitment
| Name | Model | Machine Number |
|---|---|---|
| APT4S Pump w/Skid, Cold Weather | APT4S CW | 5200019798 |
| APT4T Pump, Electric Brake, Cold Weather | APT4T CW | 5200019793, 5200019792 |
| APT4T Pump, Surge Brake | APT4T | 5200019643, 5200019644 |
| APT4S Pump w/Skid | APT4S | 5200018977 |
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.
