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Description
The Garmin GT8HW-IH In-Hull Transducer delivers reliable, high-speed depth readings for fiberglass bass boats without transom mounting. Using high-wide CHIRP sonar and 250W power, it provides clear depth performance even at planing speeds. Ideal for anglers who want accurate sonar data with a clean, in-hull installation.
Garmin GT8HW-IH In-Hull Transducer Item # 1000591
Description
GT8HW-IH transducer is ideal for bass boats that want to install the transducer inside a fiberglass hull and not on the transom where cavitation could cause issues. It requires a flat section (less than 6°) in the hull to be mounted and is excellent for boats traveling at high speeds that want to maintain accurate depth readings.
Features:
- 8-pin transducer offers high-wide CHIRP traditional sonar (145-230 kHz) and has a power rating of 250W
- May be used in conjunction with a GT30-TM transducer and an adapter cable so you can maintain depth at high speeds and scanning capabilities at trolling speeds
- For installation, follow the included instructions carefully to avoid damaging your boat
Specifications:
- Frequency: CHIRP High Wide (145-230 kHz)
- Power: 250W
- Beamwidth: 24°-16°
- Maximum depth: 800'
- Cable length: 20'
- Transducer depth/speed/temperature: Depth
- Number of pins: 8-pin
- Supported deadrise/transom angles: 0°-6° deadrise
Included:
- GT8HW-IH transducer
- In-hull fitting
- Documentation
Part Numbers for Garmin GT8HW-IH In-Hull Transducer
Reviews
Rated 4 out of
5
by
Anonymous from
In-Hull Transducer
My new Garmin Chartplotter came with a flip-up transom-mounted transducer. I have always used, and much prefer, an in-hull shoot-through transducer, for which I have installed a 4” PVC tube in the bilge, into which I drop the transducer, then fill it with water, coolant, or mineral oil, sealed off with a 4” pipe plug that I slotted to accommodate the transducer cable. Even though this transducer is not intended to work inside a hill with more than a few degrees slope, and my Newport 30 has around 12 degrees, I tested it’s accuracy with a lead line, and found it was within two feet of actual depth - close enough for me! I am aware that Garmin offers another transducer with a variety of shims (?) to accommodate different hull slopes - but I didn’t want to spend an extra $100 for that feature. Happy with the results I got with this one!
Date published: 2026-07-06