Boat Thruster Guide

What to buy, what it costs, what it takes to fit

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Thruster specs

Sideshift SD230: specs, price and the boats it fits

The SD230 gives a sterndrive boat up to 30 ft steering at the stern, with no hole in the hull. It bolts to the flat plate above the drive’s propeller and turns with the drive, so the push follows the wheel. You can fit it with the boat afloat, on 12 V. Sideshift launched this mount in 2020. It costs $4,495.

Ask your engine dealer about the drive’s warranty before you drill the plate. Then add a starting battery, cable and a charger to finish the install. They don’t come in the box and add about $601 to $677, as the cost estimate below shows.

When you’re on plane, trim the drive so the unit rides just clear of the water. Trimmed wrong, the manual warns, it steers heavy and the unit can be damaged.

Over time the shaft seal is what wears. Owners of Sideshift’s bow and stern units report seal failures at seven or eight years. It runs full on or off, in pushes of 3 to 5 seconds, with 20 to 30 seconds the most the manual allows. A replacement motor is $995. The warranty is two years, parts only.

Installers will find the wiring figures and dimensions further down. For the rest of Sideshift’s line, read the Sideshift thruster review.

Where this summary comes from (8 sources, read 11 October 2026)

Key facts

  • DIY level 4 of 5 You fit it, electrician connects
  • Thrust Not published Our sizing works from the motor's rating
  • Boat length Up to 30 ft Sideshift's own range
  • Price $4,495 full kit, sideshift.com, 28 August 2026
  • Fitted by a yard $6,384 to $8,784 Our estimate at 24 to 33 ft, unit and job
  • Voltage 12 V As sold
  • Mounts External Fixed mount, stern
  • To fit it Afloat The maker says it goes on in the water
  • Run limit Bursts of 3 to 5 seconds Never more than 20 to 30 seconds at a time

Every figure here is the maker’s or a dealer’s, except the fitted cost, which is our estimate. The full spec sheet is further down.

How much of the install is yours

DIY 4 of 5: You fit it, electrician connects. You mount and wire it; a marine electrician makes the final connections.

DIY levels

  • Level 5: Owner install. No yard, no electrician.
  • Level 4: You fit it, electrician connects. You mount and wire it; a marine electrician makes the final connections.
  • Level 3: Split with the yard. The yard does the below-waterline part; you do the wiring.
  • Level 2: Wiring prep only. The yard fits the unit and does the hull work; you do the wiring prep.
  • Level 1: Yard job. A qualified professional does all of it.

You Yard Electrician. The bar is labor hours; a haul-out is a note.

How we rate DIY

You: 6 to 8 h Yard: none Electrician: 2 to 4 h No haul-out.

  1. Mount the thruster; fit the battery, controller and joystick; run the cables You 6 to 8 h Sideshift’s own figure: 6 to 8 hours per thruster, depending on the wire runs. Every mount and connection is above the waterline. Source.
  2. Final connections at the battery and the motor, load test Electrician 2 to 4 h Our estimate. Nobody publishes a time for the final connections and test on their own.

Your part needs:Drilling above the waterlineHeavy battery cableCrimping big lugs

A qualified marine electrician should make the final connections and test them before first use. Hours are labor only.

Is it right for your boat?

What Sideshift says Up to 30 ft The maker's own range, from its listing
What our sizing says 24 to 33 ft On our estimate from the motor, across the kinds of boat it fits

Sideshift prints no thrust, so our sizing uses an estimate from the motor’s rating. That estimate can say a boat is too big for it. It cannot promise a fit. The maker gives one range for every boat.

The table below tries the Sideshift SD230 Sterndrive Stern Thruster on each kind of boat, at every length that kind of boat is built in. The wind is 15 knots and the rules are the finder’s own. A length counts as a fit when the unit gives the thrust that boat needs where it mounts and the maker lists it for that length.

A boat up to 10 percent past the maker’s range still counts here, as it does in the finder. So the table runs up to 33 ft, just past Sideshift’s own range (up to 30 ft).

The Sideshift SD230 Sterndrive Stern Thruster against each kind of boat, in a 15 knot wind. Our sizing, from the finder’s own rules.
Boat Lengths it fits, on our estimate
Pontoon & tritoon Not listed. Its maker sells it for another kind of boat.
Sailboat Not listed. Its maker sells it for another kind of boat.
Houseboat Not listed. Its maker sells it for another kind of boat.
Catamaran Not listed. An external unit bolts to the side of a single hull at the bow or to its transom, and a cat has two narrow hulls with a bridgedeck between them, so there is nowhere forward to hang one.
Trawler Not listed. Its maker sells it for another kind of boat.
Motor yacht Not listed. Its maker sells it for another kind of boat.
Bass & flats Not listed. Its maker sells it for another kind of boat.
Wake & ski boats Not listed. Its maker sells it for another kind of boat.
Express cruiser 24 to 33 ft
Center console Not listed. Its maker sells it for another kind of boat.

It is sized for one kind of boat here. For your own boat, the finder gives an answer that also counts your drive and who does the fitting. The compare page sets this unit beside others.

What it costs fitted

These totals are our estimate of a yard job: the unit’s price, plus a yard’s hours at $160 to $180 an hour, plus the batteries, cable and charger, plus the other parts the box does not hold. The hours come from what owners and yards report. Your own yard will have its own opinion. The cost page builds the same figures line by line.

  • The unit$4,495
  • Yard labor$1,280 to $3,6008 to 20 hours
  • Batteries, cable, charger$601 to $677
  • Other parts$8 to $12
  • Total, 24 to 33 ft$6,384 to $8,784Our estimate

The Sideshift SD230 Sterndrive Stern Thruster fitted by a yard. It comes to the same at every length it is sized for. Our estimate.

How the batteries, cable and charger add up. We price a battery bank close to the thruster, as the makers recommend, with 10 to 20 ft of cable out and back: red for the positive, black for the negative, cut to length. The low end is the cheapest battery that meets the figure and the shorter run; the high end is a sealed (AGM) battery and the longer run. The charger is a NOCO GEN5X2 two-bank shore charger.

Batteries and lugs are priced at Fisheries Supply and the cable and charger at Defender, read 12 October 2026.

  • At 12 V: one 12 V battery, at least 850 CCA (Sideshift’s minimum), $360 for the battery; Sideshift’s cable table gives 1/0 AWG: $95 to $171 for the red and black cable and the lugs; a GEN5X2 charger, $146.

Fitting it yourself. Tell the finder you will fit a Sideshift yourself and it takes the yard’s labor off. With that off, the total is $5,104 to $5,184. That is the unit plus the batteries, cable and other parts, which you buy whoever does the fitting.

The sizing and the costs on this page are estimates, for guidance only and without warranty. They are no quote, and nobody has inspected your boat. Check them against the maker’s manual and your yard before you rely on them. Terms of use.

What else you buy

What follows comes from Sideshift’s Monohull installation manual Rev 3.1, November 2025, read 30 September 2026.

In the box
The thruster, the motor controller, the wireless joystick and its receiver, a wireless key fob, the wiring harness and mounting hardware, the fuse in a holder with a digital voltage display, and a battery switch. Sideshift lists these on each product page. The manual adds the crimper, anti-seize, Loctite, Sikaflex and heat shrink.
Bought separately
The batteries, the 1/0 or 2/0 battery cable and the charger. The joystick is wireless: no wire runs from it to the thruster. It still needs 12 V at the helm for its own power, so plan a small feed there.
Charging
The thruster gets a bank of its own: cranking type, 850 cold cranking amps per battery, within 10 ft of the controller. You buy the charger too, either a shore charger or a DC-to-DC charger fed off the bank the alternator charges.

The manual’s words, page 40: “The 2 most popular ways are: AC/DC multi-bank charger such as the NOCO GEN5X2 (available in our online store). ... Using a DC-DC Isolated Charger such as the Victron Orion-Tr DC-DC Converters Isolated.”

The “other parts” line in the estimate above is the priced parts below, $8 to $12 at Fisheries Supply’s prices on 30 September 2026. The batteries, cable and charger have a line of their own.

Parts the Sideshift SD230 Sterndrive Stern Thruster’s box leaves to you, from the makers’ manuals read 30 September 2026. “What to ask for” is Sideshift’s own part or model where its manual names one, otherwise the dealer’s item.
Part What it is What to ask for Dealer price
Control-circuit fuse and switch A small fuse, and often a switch, on the thin wire that powers the panel or control box. Sideshift names none $8–$12Blue Sea in-line ATO fuse holders, at Fisheries Supply, read 16 October 2026.
Battery cable and lugs The two heavy cables from the battery to the motor, sized to the length of the run. The wiring calculator sizes them. 1/0 AWG (230 series) or 2/0 AWG tinned battery cable In the electrical line
Battery bank A cranking-type bank near the motor, sized by the maker's cold cranking amps. The battery calculator checks it. Sideshift names none In the electrical line
Charger or charge feed How the thruster bank gets charged: a shore charger of its own, a DC-to-DC charger or charging relay from the boat's system, or a charger built into the unit. NOCO GEN5X2, or a Victron Orion-Tr Smart isolated DC-DC charger $146–$305NOCO GEN5X2 shore charger, Victron Orion-Tr Smart DC-DC charger, Blue Sea ML-ACR charging relay, at Fisheries Supply.

The cost page has the whole list with what every maker says about each part.

For the yard and the installer

The full spec sheet, grouped the way a yard reads it. Every figure is the maker’s or a dealer’s, with its source.

The Sideshift SD230 Sterndrive Stern Thruster, every published figure the site holds, with where each came from.
Thrust and motor
Thrust Not published
Motor1.86 kW
Voltage12 V
Fitting
TypeExternal, fixed mount
End of the boatStern
What it does to the hullThree small holes, all above the waterline
Haul-out to fit itNo: the maker says it goes on afloat
DriveMounts on a sterndrive only.
Maker’s boat lengthUp to 30 ft
Price and ordering
Price $4,495 full kit, the maker's own price, sideshift.com, 28 August 2026
Part number Not held for this listing
Documents
Manual Installation manual (PDF)on the maker's site
Warranty Sideshift gives 2 years against faulty workmanship or materials. Its exclusions include wrong wire size or low voltage, burn-out from overuse, collisions, and tangled line or netting. installation manual, Rev 3.1, p. 68
The site’s reviewSideshift thruster review

Draw, cable, fuse and battery, at each voltage

These are the maker’s own figures, at each voltage it is sold at. The cable is the size for the shortest run in the maker’s table. A longer run may need heavier cable, and the wiring calculator works that out for your own boat.

The Sideshift SD230 Sterndrive Stern Thruster’s draw, cable, fuse, battery and run limit, as the maker publishes them.
Voltage Draw Maker’s cable Fuse Battery Run limit
12 V 300 Astart current 1/0 AWG. The manual keeps the run to 10 ft of cable counted out and back. The FAQ allows the battery up to 30 ft from the controllerinstallation manual, Rev 3.1 Not published 850 CCA minimum, as one 12 V starting batterySideshift installation manual, Rev 3.1, p.39, and the FAQ bursts of 3 to 5 seconds, never more than 20 to 30 seconds at a timeinstallation manual, Rev 3.1

What holds up and what to weigh

Each point names the fact it rests on.

What holds up

  • It goes on with the boat in the water. No haul-out is needed to fit it.Sideshift: "All Sideshift thrusters can be installed in-water since all the mounting locations and cable connections are routed above the waterline."

What to weigh

  • Sideshift publishes no thrust figure for it. The boat table uses our estimate from the motor's rating.The maker's published specs
  • It runs in bursts of 3 to 5 seconds, never more than 20 to 30 seconds at a time.installation manual, Rev 3.1

What the manual and listings say

This is the note we keep on the Sideshift SD230 Sterndrive Stern Thruster, written from the maker’s manual, its product pages and the dealer’s listing.

In the box: The kit has the thruster, the controller, the wireless joystick and key fob, the harness, the fuse and a battery switch. You buy the batteries, the cable and a charger. The joystick is wireless but needs 12 V at the helm for its own power.

Our note

Bolts to the sterndrive's cavitation plate, so nothing goes through the hull. It goes on with the boat afloat. It runs on one 12 V starting battery of 850 cold cranking amps on 1/0 AWG cable, up to 30 ft from the controller. At planing speed the manual has you trim the drive so the thruster rides just above the surface.

Trimmed wrong, it steers heavy and can damage the unit. The unit pushes on the drive behind the point it steers on, so it can try to turn the drive and the wheel with it. Keep a hand on the wheel while you use it.

Bursts only: the manual asks for pushes of 3 to 5 seconds as normal practice, and never more than 20 to 30 seconds at a time. Its warranty does not cover a motor burned out by overuse. On 17 September 2026 sideshift.com was running an end of summer sale, with ten percent off every thruster. The price here is the list price. The sale was still on when the page was read again on 2 October 2026.

Videos

Two of Sideshift’s own videos, from its YouTube channel: an outboard or sterndrive stern kit going on, then the boat on the water, and the whole install, in four minutes. They are the maker’s pitch. Watch them for what the unit looks like and how it goes in, and take any claim back to the figures above.

Sideshift’s own video, on Sideshift’s YouTube channel. The picture is a still from it.
Sideshift’s own video, on Sideshift’s YouTube channel. The picture is a still from it.

Other sizes and close alternatives

These are Sideshift’s next sizes in the same line, by thrust.

Sideshift prints no thrust, so we name no other maker’s unit as its match. The compare page lists every model.

Every model with a page here is listed, maker by maker, on the thruster index.

Where to go next

The specs are the maker’s and the dealers’, on the dates shown. The sizing and the costs are our arithmetic, done without seeing your boat.