Multiquip 338040290 Gearbox Assembly Complete 2-Inch

The Multiquip 338040290 Gearbox Assembly Complete 2-Inch is a genuine OEM component designed for MQD2HA and MQD3HA diaphragm pumps. Sourced directly from Multiquip, this assembly delivers the exact tolerances and gear engagement required to keep your pump running at full capacity. It is a direct replacement unit confirmed for MQD2HA and MQD3HA models, so you can install with confidence knowing the fitment has been verified against the original equipment specifications. When a gearbox wears or fails, pump output drops and the diaphragm drive cycle becomes inconsistent — replacing it with genuine OEM part 338040290 restores correct operation without guesswork.

Key Features

• Genuine OEM Gear Tolerancing — Manufactured to Multiquip's original gear mesh and backlash specifications, ensuring smooth, consistent torque transfer through the pump drive.
• Complete Drop-In Assembly — Supplied as a fully assembled gearbox unit, eliminating the need to source and match individual internal components before installation.
• Confirmed Fitment for MQD2HA and MQD3HA — Verified against Multiquip's parts documentation for both diaphragm pump models in this series.
• Restores Full Pump Drive Performance — A worn or damaged gearbox causes erratic diaphragm stroke and reduced flow; this replacement brings output back to rated specification.
• 2-Inch Drive Configuration — Sized specifically for the 2-inch pump drive interface on these models, maintaining the correct speed and torque ratio for the diaphragm mechanism.

The gearbox assembly on a diaphragm pump converts engine power into the precise reciprocating motion that drives the diaphragm back and forth, creating the suction and discharge strokes that move fluid through the pump. Without a properly functioning gearbox, the diaphragm cannot maintain a consistent stroke rate, leading to reduced flow, pressure loss, and eventual pump failure. Replacing a worn gearbox with a complete, matched assembly like the Multiquip 338040290 ensures the diaphragm drive cycle is fully restored to its original rhythm and output.

Part Details

Compatibility & Fitment

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.