Commercial

Best Transducer Mounting Plates & Jack Plates

Updated July 2026 · FishFinders.co Editorial

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Transducer mounting plates and jack plates position the transducer in clean, undisturbed water — critical for performance at speed. Here's the equipment that makes the difference between sonar that works and sonar that cavitates out at 30 mph.

Starboard Extension Plate (Transom Mount) $

Aluminum or poly extension plates mount the transducer outboard of the motor turbulence — keeps the transducer in clean water while running. Standard on most properly rigged bass boats.

Lowrance/Garmin Adjustable Transducer Bracket $

Manufacturer-supplied adjustable transom brackets let you fine-tune transducer depth and angle without re-drilling. Match to your specific transducer model.

Trolling Motor Transducer Arm (ECHOMAP/HELIX Compatible) $

Trolling motor shaft transducer mount — positions the transducer at the bow for forward-facing sonar applications. Essential for LiveScope/Mega Live installation.

Jack Plate (Hydraulic, for Outboard Motors) $$$

A hydraulic jack plate moves the entire outboard motor up and down — raising it for shallow water, lowering it for speed and efficiency. Also moves transducer with the motor for clean sonar at all operating heights.

Why Transducer Placement Matters

A transducer in prop wash (turbulence from the motor propeller) or behind a strake (the ridges molded into the hull bottom) produces noisy, inaccurate sonar at speed. Air bubbles from turbulence appear as interference on the screen. The fix: mount the transducer ahead of the motor's prop wash zone, below any strakes, and low enough in the water that it doesn't lift out in rough water.

Frequently Asked Questions

Where should I mount my transducer on a bass boat?

On the starboard (right) side of the transom, between the motor and the hull edge, positioned so the transducer face is below the hull's running plane. Avoid mounting directly in prop wash. An extension plate that moves the transducer outboard and ahead of the motor's turbulence resolves most interference problems.

Can I mount a transducer on a trolling motor?

Yes — most major brands (Garmin, Humminbird, Lowrance) make trolling motor transducer arms that mount the transducer on the trolling motor shaft. This is required for forward-facing live sonar (LiveScope, Mega Live) where the transducer needs to point forward from the bow. The transducer travels with the motor, staying in the water even when the bow is raised.

What is a jack plate and do I need one?

A jack plate is a mounting plate between your transom and outboard motor that allows vertical adjustment of the motor height — either manually or hydraulically. Beyond improving performance in shallow water, hydraulic jack plates let you fine-tune the height for optimal top speed. Not required for most fishing, but standard on tournament bass boats.