New Mercury/Mariner 300-400 HP Verado Heavy Duty Lower Unit for Sale

Restore the performance and reliability of your outboard with this New OBR Mercury/Mariner 300-400 HP Verado Heavy Duty Lower Unit. Designed for 2006-2021 Mercury and Mariner 6-cylinder Verado engines, this premium replacement gearcase is engineered to meet or exceed OEM specifications while providing exceptional strength for demanding marine conditions.

Featuring a 1.75:1 gear ratio, this heavy-duty lower unit delivers excellent acceleration, efficient power transfer, and smooth operation across a wide range of boating applications. Whether you’re running offshore, cruising long distances, or operating under heavy loads, this gearcase is built to provide dependable performance season after season.

Each unit is professionally assembled using a combination of new OEM and premium aftermarket components, including high-grade American steel gears and shafts for maximum durability and long service life. The gearcase is equipped with a 1¼-inch propshaft and is available for 20-inch (L), 25-inch (XL), and 30-inch (XXL) standard rotation models, allowing you to select the correct configuration for your engine.

A limited two-year warranty is included for added peace of mind, with the option to purchase an additional twelve-month extended warranty for even greater protection. There is no core charge, and eligible returned cores may qualify for a refund of up to $200 after inspection.

At EZ Boats Marine, we proudly supply premium replacement lower units, gearcases, outboard motors, and marine engine components that help boat owners restore performance while reducing repair costs. Our knowledgeable team is always available to help verify compatibility before you order.

Key Features

• Brand new OBR heavy-duty lower unit
• Fits Mercury & Mariner Verado 300-400 HP engines
• Compatible with 2006-2021 6-cylinder Verado models
• Heavy-duty 1.75:1 gear ratio
• Premium OEM and aftermarket internal components
• High-strength American steel gears and shafts
• 1¼-inch propshaft
• Available for 20″, 25″, and 30″ standard rotation models
• Built for offshore, recreational, and commercial applications
• Limited two-year warranty included
• Optional 12-month extended warranty available
• No core charge required
• Eligible core returns may receive up to a $200 refund after inspection

Specifications

Product Type: Heavy Duty Lower Unit / Gearcase

Brand: OBR

Compatible Brands: Mercury & Mariner

Engine Compatibility: Verado 6-Cylinder

Horsepower: 300 HP – 400 HP

Model Years: 2006-2021

Gear Ratio: 1.75:1

Propshaft Diameter: 1¼”

Rotation: Standard Rotation

Available Shaft Lengths:

• 20″ (L)
• 25″ (XL)
• 30″ (XXL)

Water Pump: Not Included

Condition: Brand New

Warranty: Limited 2-Year Warranty

Why Buy From EZ Boats Marine?

When purchasing marine engine components, quality and reliability matter. EZ Boats Marine supplies premium outboard motors, lower units, powerheads, engine rebuild kits, and genuine-quality replacement parts for Mercury, Yamaha, Suzuki, Honda, Evinrude, Tohatsu, and other leading marine brands.

We carefully source products from trusted manufacturers so our customers receive dependable parts backed by excellent customer service. If you’re unsure which lower unit fits your engine, simply provide your engine model number and our team will help verify compatibility before purchase.

Order Your Mercury Verado Heavy Duty Lower Unit Today

Restore your outboard’s performance with this New OBR Mercury/Mariner 300-400 HP Verado Heavy Duty 1.75:1 Ratio Lower Unit. Contact EZ Boats Marine today for compatibility assistance, shipping information, or to place your order with confidence.