Multiquip EM20407 Gearbox Assembly

The Multiquip EM20407 is a genuine OEM Gearbox Assembly designed for Whiteman walk-behind power trowels including the BS90C, BH11C, BH90C, B46, JS60C, JH90C, JH55C, J36-M30 Series, BS46H11, BS46H90, JS36H90, JS36H55, and B46S90. As a direct OEM replacement, this assembly is built to the same specification as the original component, ensuring a correct installation with no guesswork on fit or function. DHS Equipment supplies this part as an authorized Multiquip OEM component, so you can order with confidence knowing you are getting the exact part your trowel requires.

Key Features

• Genuine OEM Construction — Manufactured to Multiquip's original engineering specification, delivering the same gear ratios, bearing tolerances, and housing dimensions as the part that came with your machine.
• Broad Trowel Compatibility — Fits a wide range of Whiteman walk-behind power trowels across the B, BS, BH, J, JS, and JH series, including international variants BS46H11, BS46H90, JS36H90, and JS36H55.
• Drop-In Replacement — Matches the original bolt pattern and shaft interface, allowing straightforward installation without secondary machining or custom adapters.
• Sustained Blade Drive Performance — A correctly functioning gearbox delivers consistent torque transfer to the trowel blades, maintaining smooth blade rotation and proper finishing action across the full range of pitch settings.
• Wear-Rated Internal Components — The assembly uses gear sets and bearing surfaces rated for the continuous load cycles that walk-behind concrete finishing equipment demands, resisting premature wear under sustained operation.

The gearbox assembly is the core mechanical link between the trowel's engine output and its rotating blade spider. It reduces engine speed to the correct blade RPM while multiplying torque, allowing the trowel blades to apply consistent finishing pressure to fresh concrete. When the gearbox wears or fails, blade rotation becomes uneven or stops entirely, leaving an unfinished surface and forcing machine downtime mid-pour. Replacing the gearbox assembly with a correct OEM unit restores full drive function and ensures the trowel performs as intended through every stage of the finishing process.

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.