The Wacker Neuson 5200020185 is a genuine OEM Lock Nut designed for the APT4S and APT4T pump series. This includes the APT4S Pump with Skid, APT4T Pump with Electric Brake, APT4T Pump with Surge Brake, and all corresponding Cold Weather variants. As a direct Wacker Neuson OEM component, the 5200020185 is produced to the exact tolerances and material specifications required for these pumps — no guesswork on fit or compatibility. Whether you're servicing a standard configuration or a cold weather unit, this is the correct replacement Lock Nut for the job.
Key Features
- Precision-Threaded OEM Construction — Manufactured to exact thread pitch and torque specifications, ensuring the Lock Nut seats and holds correctly within the pump assembly without over-tightening risk.
- Drop-In Replacement — Matches the original fastener profile for straightforward installation on APT4S and APT4T pumps, including skid-mounted and braked configurations.
- Broad APT Series Fitment — Compatible across six APT4 pump configurations: APT4S Pump with Skid, APT4T with Electric Brake, APT4T with Surge Brake, and all three Cold Weather variants.
- Maintains Secure Assembly Integrity — A properly torqued lock nut prevents loosening under vibration and operational load — critical on trailer-mounted pump units exposed to road and job site movement.
- Genuine Wacker Neuson OEM Part — Sourced directly through the Wacker Neuson parts network, this component meets the same material and dimensional standards as the original hardware installed at the factory.
A lock nut is a specially designed fastener that resists loosening when subjected to vibration, torque, and dynamic loads. On pump assemblies like the APT4S and APT4T series, lock nuts are used at critical connection points where standard fasteners could work themselves loose over time due to engine vibration or movement during transport. When a lock nut fails or is missing, it can allow components to shift or separate, leading to misalignment, leaks, or mechanical damage. Replacing a worn or damaged lock nut promptly keeps the pump assembly properly secured and operating as intended.
Part Details
| Part Number | 5200020185 |
|---|---|
| Brand | Wacker Neuson |
| Part Type | Genuine OEM |
| Description | Lock Nut |
Compatibility & Fitment
| Name | Model | Machine Number |
|---|---|---|
| APT4S Pump w/Skid | APT4S | 5200018977 |
| APT4T Pump, Electric Brake | APT4T | 5200019644, 5200019643 |
| APT4S Pump w/Skid, Cold Weather | APT4S CW | 5200019798 |
| APT4T Pump, Electric Brake, Cold Weather | APT4T CW | 5200019793, 5200019792 |
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.
