The Wacker Neuson Spring is a genuine OEM Spring designed for the APT4S and APT4T pump series, including surge brake, electric brake, and cold weather variants. As a direct OEM replacement, this spring is sourced from Wacker Neuson and manufactured to the same specifications as the original component — ensuring a drop-in fit with no guesswork on compatibility. It covers the full range of APT4 pump configurations, making it a reliable choice whether you're servicing a standard APT4S pump with skid or a cold weather APT4T electric brake unit. Keep part number on hand to avoid unnecessary delays during routine maintenance or field repairs.
Key Features
- OEM Spring Tension Integrity — Manufactured to the exact load and deflection characteristics of the original, so the spring performs its designed mechanical function without over- or under-tensioning.
- Direct Drop-In Replacement — Matches the original mounting geometry and free length, fitting directly into the APT4 pump assembly without rework or adjustment.
- Broad APT4 Series Coverage — Compatible with APT4S and APT4T pump models, including surge brake, electric brake, and cold weather configurations.
- Consistent Pump Operation — A correctly tensioned spring maintains proper component engagement within the pump mechanism; a worn or fatigued spring can cause erratic operation or premature wear on adjacent parts.
- Brake System Relevance — This spring supports models equipped with surge and electric brake systems, making correct spring specification important to safe brake function and towing compliance.
A spring within a pump assembly serves as a mechanical force element — applying consistent tension or return force to keep moving components properly engaged, seated, or reset during each operating cycle. In trailer-mounted pump units like the APT4 series, springs are often integral to brake actuator mechanisms or valve return functions, where precise spring rate directly affects how reliably the system responds. When a spring fatigues, takes a set, or breaks, the affected mechanism may fail to return to its rest position, causing performance inconsistency or, in brake-related applications, a safety concern.
Part Details
| Part Number | 5200019889 |
|---|---|
| Brand | Wacker Neuson |
| Part Type | Genuine OEM |
| Description | Spring |
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.
