The Wacker Neuson Oil Seal is a genuine OEM component designed for the APT4S and APT4T pump series, including surge brake, electric brake, and cold weather variants. As a factory-sourced part, is produced to the exact material and dimensional standards of the original seal, ensuring a correct, leak-free installation. This oil seal fits across the full APT4S and APT4T lineup — covering standard and cold weather configurations — making it a straightforward replacement for scheduled maintenance or wear-related service.
Key Features
- OEM-Grade Seal Material — Manufactured to the original compound and compression specification, delivering the same fluid retention performance as the factory-installed seal.
- Drop-In Replacement — Matches the original bore diameter and seating profile for a direct swap with no additional machining or modification to the pump housing.
- Broad APT Series Coverage — Compatible with APT4S and APT4T pumps across surge brake, electric brake, and cold weather configurations, including skid-mounted variants.
- Prevents Fluid Loss and Contamination — A healthy oil seal keeps lubricant in and debris out; a worn seal leads to oil leaks, bearing contamination, and accelerated internal wear.
- Fluid System Integrity — Maintaining a sound oil seal is critical to pump reliability; failure can allow fluid ingress that degrades internal components and compromises pump output.
An oil seal is a precision ring fitted at rotating shaft interfaces to retain lubricating oil inside the housing while blocking dirt, water, and other contaminants from entering. In a water transfer pump like the APT4S and APT4T series, the seal protects the internal bearing and gear assemblies that keep the pump running smoothly under continuous load. When an oil seal deteriorates — through heat cycling, age, or mechanical wear — it begins to leak, starving lubricated surfaces and allowing abrasive particles inside, which can rapidly escalate into costlier internal damage if not addressed promptly.
Part Details
| Part Number | 5200019881 |
|---|---|
| Brand | Wacker Neuson |
| Part Type | Genuine OEM |
| Description | Oil Seal |
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.
