The Wacker Neuson Lock Nut 1/2 is a genuine OEM fastener designed for the APT4T, APT6T, and APT8T pump series, covering both surge brake and electric brake configurations, including cold weather variants. As a direct OEM replacement sourced from Wacker Neuson, part is manufactured to the exact specifications of the original hardware installed at the factory. This lock nut fits across the full APT pump lineup, making it a versatile stock item for operators and service technicians who maintain multiple units in the field.
Key Features
- Genuine OEM Fastener Integrity — Manufactured to exact thread pitch and locking-element specifications, ensuring the same clamping force and vibration resistance as the original hardware.
- Drop-In Hardware Replacement — 1/2 inch sizing matches the original fastener location directly, so installation requires no rework of surrounding hardware or mating threads.
- Broad APT Series Coverage — Compatible with APT4T, APT6T, and APT8T pumps in surge brake, electric brake, and cold weather configurations — a single part number serves the entire pump family.
- Vibration-Resistant Locking Design — Lock nut construction prevents loosening under the operational vibration typical of trailer-mounted pump equipment, maintaining connection integrity over extended service cycles.
- Verified OEM Part Number — Ordering by Wacker Neuson part number 5000178412 confirms you are receiving the correct fastener for your specific APT pump configuration.
A lock nut is a fastener engineered to resist loosening when subjected to vibration and dynamic loads. Unlike a standard hex nut, a lock nut incorporates a locking feature — such as a nylon insert or a distorted thread profile — that creates additional friction against the mating thread, keeping the connection secure during operation. On trailer-mounted pump equipment like the APT series, where road vibration and pump operation combine to stress fastened joints continuously, a properly functioning lock nut is essential to maintaining structural and mechanical integrity. A loose or failed lock nut can allow connected components to shift or separate, leading to equipment damage or unsafe operating conditions.
Part Details
| Part Number | 5000178412 |
|---|---|
| Old Part Number | 0178412 |
| Brand | Wacker Neuson |
| Part Type | Genuine OEM |
| Description | Lock Nut 1/2 |
Compatibility & Fitment
| Name | Model | Machine Number |
|---|---|---|
| APT6T Pump, Surge Brake | APT6T | 5200019646, 5200019647 |
| APT6T Pump, Surge Brake, Cold Weather | APT6T CW | 5200019794, 5200019795 |
| APT4T Pump, Surge Brake | APT4T | 5200019643, 5200019644 |
| APT8T Pump, Surge Brake | APT8T | 5200019648, 5200019649 |
| APT4T Pump, Surge Brake, Cold Weather | APT4T CW | 5200019792, 5200019793 |
| APT8T Pump, Surge Brake, Cold Weather | APT8T CW | 5200019796, 5200019797 |
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.
