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Sea Ray SLX 310 OB (2017-)

2 x 350-hp Mercury Verado

Brief Summary

Sea Ray’s SLX 310 OB is designed with a layout that prioritizes comfort and a social seating arrangement. The SLX 310 OB doesn’t just look to entertain with a socially optimized and accommodating layout; it looks to entertain via creation of an environment. By eliminating the sterndrive engines, which traditionally have powered boats of this size and type, Sea Ray has created more internal space for storage as well as improved performance by moving propulsion aft.

Key Features

  • Iconic styling with elegant hull sculpting, available in multiple color configurations
  • Expansive cockpit space with standard wet bar
  • Luxurious and plush seating with abundant storage beneath
  • Dual seating at Helm and Companion side
  • Spacious and luxurious head compartment
  • Comfortably seats 17 people while underway
  • Standard Dual Touch Screen Electronics Display, enabling multiple control functions
  • Standard Electric Tower with articulating bimini system
  • Optional State of the Art equipment such as Submersible Hydraulic Swim Platform, Fiberglass Hardtop and optional Sureshade, Dynamic Running Surface

Test Results

600 3 2.6 1.4 2.1 1.9 335 291.4 60
1000 5.5 4.7 2.5 2.2 1.9 343 298.6 67
1500 7.9 6.9 4.2 1.9 1.7 300 260.7 67
2000 9 7.8 7.3 1.2 1.1 194 169.1 74
2500 11.5 10 11.7 1 0.9 155 134.6 76
3000 16.6 14.4 15 1.1 1 174 151.6 81
3500 23.6 20.5 17.4 1.4 1.2 213 185.4 82
4000 31.9 27.7 20.1 1.6 1.4 250 217 82
4500 39.8 34.6 28.4 1.4 1.2 220 191.7 84
5000 46.2 40.2 38.9 1.2 1 187 162.7 85
5500 49.5 43 54.8 0.9 0.8 142 123.7 88
5900 53.4 46.4 61.4 0.9 0.8 137 119 90


Length Overall 31' 6'' / 9.6 m
Beam 10' 2''
3.1 m
Dry Weight 10,335 lbs.
4,699 kg
Tested Weight 11,187 lbs.
5,074 kg
Draft Up 28''
71 cm
Draft Down 38''
96 cm
Deadrise/Transom 21-deg.
Bridge Clearance N/A
Person Capacity 17
Fuel Capacity 130 gal.
492 L
Water Capacity 24 gal.
90 L
Total Weight 11,187 lbs.
5,074 kg


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Acceleration Times & Conditions

Time to Plane 4.7 sec.
0 to 30 10.5 sec.
Ratio N/A
Props 19 p Revolution
Load 2 persons, 2/5 fuel, no water, 50 lbs. of gear
Climate 72 deg., 64 humid.; wind: 10-15 mph; seas: light chop

Engine Options

Tested Engine 2 x 350-hp Mercury Verado
Std. Power 2 x 300-hp Mercury 300XL Verado FourStroke
Opt. Power 2 x 300-hp Mercury 300XL Verado FourStroke Outboards
2 x 300-hp Mercury 300XL Verado® FourStroke Outboards
2 x 350-hp Mercury 350XL Verado FourStroke Outboards
2 350-hp Mercury 350XL Verado FourStroke Outboards
2 x 350-hp Mercury 350XL Verado FourStroke Outboards

Captain's Report


The Sea Ray SLX 310 OB has a LOA of 31’6”, beam of 10’2”, and is pleasure boat certified for passenger capacity.


Sea Ray’s SLX 310 OB is designed with a layout that prioritizes comfort and a social seating arrangement. The SLX 310 OB doesn’t just look to entertain with a socially optimized and accommodating layout; it looks to entertain via creation of an environment.

By eliminating the sterndrive engines, which traditionally have powered boats of this size and type, Sea Ray has created more internal space for storage as well as improved performance by moving propulsion aft.


An overhead view of the SLX 310 OB. Seen here, the SLX 310 OB’s core strength is its seating layout.

Major Features

  • Outboard Power. By converting the 310 from a sterndrive to outboard power, the builder is accommodating buyers who prefer outboards. It also opens up storage space where the sterndrive engines would normally go.


A look at the digital throttle control, which is standard on the SLX 310 OB. The digital side of this piece of equipment means greater responsiveness.
  • Digital Throttle Control. Digital Throttle Control comes standard on the SLX 310 OB and delivers smoother shifting, easier docking, more immediate throttle response, and in-depth information displays. Digitizing this process brings greater reliability and responsiveness. Additionally, joystick propulsion -- yet another step in improving predictability and ease of navigation -- comes as an option.
  • Custom Trailer. A trailer comes standard.
  • Five-year Stem-to-Stern Warranty. This is a factory-backed, non-declining program that includes the engine and all components. This is an unusual warranty, heretofore only offered by a few premium builders.


A look at the SLX 310 OB’s sleek tower, which can retract and rise with electrical actuation.
  • Power Tower. The versatility of the SLX 310 OB’s electric tower is a major part of its entertainment-centric design. Easily raised/lowered via an electrically articulating bimini system. This can be further outfitted by an optional fiberglass hardtop.


A visual of the Dynamic Running Surface technology, which can be programmed with ideal settings for watersports.
  • Dynamic Running Surface. The SLX 310 OB utilizes large, triangular planes set into the hull to create an articulated running surface that improves acceleration, reduces bow rise, and keeps the boat at optimal trim, according to the builder. The Dynamic Running Surface system does this automatically. Further, the system allows for recording presets, perfect for calling up an individualized wake for skiers and wakeboarders.


The enclosed head on the SLX 310 OB has plenty of headroom with a modern, clean design.
  • Enclosed Head. The SLX 310’s enclosed head is notably spacious -- ample headroom, a granite countertop, sink, mirror, and a porthole -- and helps expand the type of excursions the SLX 310 OB can tackle.
  • Solid Surface Countertop Wet Bar. The SLX 310 OB’s cockpit wet bar has a solid-surface countertop with sink and faucet and the ability to upgrade it with either of a grill or refrigerator with pull-out drawers.
  • Swim Platform. With the aft-facing lounge seating, the SLX 310 OB’s swim platform is a big part of its entertainment profile. It’s a large swim platform, integrated with a manual swim step that blurs the line between water and boat when anchored and relaxing. Optional non-skid pad or teak flooring available as well.

Features Inspection



The bow seating space with removable side-mounted table. Note the forward-facing backrests. The center space can be filled with a dedicated cushion, converting this into a huge sunpad.

Bow seating lounge. The bow seating lounge on the SLX 310 OB has the familiar touch of being optionally converted to either sunpad with a filler cushion or augmented with a mountable cocktail table. The U-shaped seating section is lined with plush bolsters along the gunwales as well as two forward facing backrests that have armrests at each end. Recessed grab rails and speakers are also in place. The windlass locker is at the peak of the bow.

The bow also has an in-deck storage locker as well, accessed via a small latch on the bow deck.



The SLX 310 OB’s LED-lit dash, with a simple, easy to navigate design. Note the faux leather on the top brow, and the cup holders.

Sleek, LED-lit dash. The dash on the SLX 310 OB is stylish with LED lighting along the edges of the panels to light up the electronics and gauges in the dark, and an intuitive layout with new twists on familiar readouts. This includes a custom Sea Ray SmartCraft that has glass lenses and chrome bezels. The visor on the dash has leather accents and also holds two cup holders. The helm station has a lockable glove box just below the dash as well.


The SLX 310 OB’s Dynamic Display utilizes two touchscreens to connect the helm with all of the boat.

Dynamic Display. The SLX 310 OB comes standard with the Dynamic Display readout, spread over two Medallion touchscreen displays of 12” and 7”. The Dynamic Display offers connectivity with and control over multiple systems -- navigation, audio, engine, lighting, and many more. Further, the SLX 310 OB comes standard with the Digital Throttle & Shift system, which offers a digitized, reliable response improving shifting, and docking maneuvers.

The dash includes a speedometer, systems tachometer that covers depth, water temperature, engine alarm, fuel consumption and usage readout, trim level, troll control, and digital speed.


The companion seat can swivel and face aft. It is directly in front of the day head hatch.


The enclosed head on the SLX 310 OB has a sink and faucet, mirror, non-skid decking, and a portlight.

Helm seating and day head. The captain’s chair is a double-wide seat with flip-up bolsters and arm rests. The companion seat to port is double-wide as well and also features flip-up bolsters as well as the ability to swivel back toward the cockpit seating section. The companion seat faces a console with a lockable glove box just above the big latch for the day head.

The head has a step-down improving headroom, and the door is lockable. The head has a solid surface countertop, stainless steel sink and faucet, vacu-flush head, portlight, storage, and non-skid floor treatment.

Finally, the helm also has a storage compartment just under its console, accessible from the aft bow cushion on the starboard side, which flips up and offers storage racks and straps, a light, and a door to the backside of the dash instruments.



A view from the stern facing forward with the cockpit seating in full view. Note the wet bar to starboard and the helm companion’s seat facing aft.


The cockpit wet bar, which sits to starboard just near the transom walkthrough. Note the full sink and faucet on the aft side of the bar.

Cockpit seating space. The cockpit space is largely taken up by the L-shaped dinette, a large, comfortable space that is one of boat’s central features. There seating comes in two places, broken up only for flow from one part of the boat to the next. The larger of the two extends along the transom and then forward along the portside of the boat.

A large table comes standard here and is serviced as such by the wet bar on the starboard side, which has a solid-surface countertop with a full sink and faucet under the liftable countertop.

The wet bar can also be upgraded with either of a grill or refrigerator with drawers.

The second part of the cockpit seating is smaller, facing aft just up against the back of the captain’s chair and extending just to where the wet bar sits.

Cockpit storage options. The cockpit has storage via side panels, as well as an in-deck locker in between the helm and cockpit sized for wakeboards and skis. This storage compartment lifts with gas-assisted struts on the latch and has vinyl matting as well. The transom walk-through space has a hatch that lifts to access a removal tub.



The aft facing sunpad/seating. Note the bottom slides forward, transforming to the sunpad. The grab rail at the bottom lifts to reveal bulk storage.

Aft-facing bench seat and sunpad lounge. Moving from the cockpit to the stern via the starboard side transom walk-through, we reach the aft-facing bench seating looking out over the aft swim platform. The seating is versatile -- it can stretch forward to make a large sunpad lounging space or flip-up to shape itself more into a plush-upholstered bench seating space. Lifting up under the entirety of the seating reveals another large storage space.

The swim platform is larger than many and combines with the aft-facing lounge to create a water-play friendly space when anchored. It has an under-mount ladder and manual swim step. Add the stainless-steel ski-tow, and Dynamic Running Surface preset capability and the SLX 310 OB can easily produce a stable ride with an ideal wake for watersports.



The twin Mercury 300XL Verado four stroke engines in white are one of several options for power on the SLX 310 OB.

The SLX 310 OB has four different options for propulsion (six when you include color choice), some of which offer the ability to include the joystick docking control. The joystick docking control makes navigation in tight spaces much easier and responsive. Here’s what Sea Ray offers in terms of power options:

  • Twin Mercury 300XL Verado FourStroke Outboards with Joystick Piloting (300-hp)
  • Twin Mercury 300 Verado FourStroke Outboards (STANDARD – 300-hp)
  • Twin Mercury 350XL Verado FourStroke Outboards with Joystick Piloting (350-hp)
  • Twin Mercury 350XL Verado FourStroke Outboards (350-hp)


The Sea Ray SLX 310 OB has a LOA of 31’6” (9.60 m), a beam of 10’2” (3.10 m) and a draft of 32” (81 cm). With an empty weight of 10,335 lbs. (4,688 kg), 41% fuel and two people, we had an estimated test weight of 11,187 lbs. (5,074 kg).

With a pair of 350-hp Mercury Verados turning 19p revolution props, we reached a top speed of 53.4 mph at 5900 rpm. Best economic cruise came in at 4000 rpm and 31.9 mph. At that speed, the 20.1 gph fuel burn translated into 1.6 mpg and a range of 250 statute miles, all while still holding back a 10% reserve of the boat’s 175-gallon (662.4 L) total fuel capacity.


In acceleration tests, the bow comes up 7-degrees before settling in to her 5-degree bow high cruise attitude after reaching planing speed in 4.7 seconds. With the power left at full throttle, we continued accelerating through 20 mph in 7.2 seconds and passed 30 in 10.5 seconds.

Of course we had calm water on our test day so we can’t comment on how she handles chop, but crossing the wake of our camera boat had her pushing through with minimal effect and no pounding whatsoever.

In turn tests, she rolls 17-degrees with the helm hard over. She will throw a wall of water in performance turns as a testament to how well she holds her track, rather than sliding along the turn. She’ll crank around in a little over her length and chine walk is minimal even when maneuvering through self-generated turbulence.

When it came time to head back, we wanted to see how she handles with the Axius joystick. And no surprise, she was dialed in perfectly to the joystick. We noticed a zero lag time between joystick inputs and response, and there was an even balance between the bow and stern with neither one tending to overtake the other.

Options to Consider


The Sea Ray SLX 310 OB is comparatively light on the add-ons, instead packing the boat with amenities as standard. Here are a look at some of the more relevant options to choose from.
  • Fiberglass Hardtop with Lights and Anchor ($6,308)
  • Hardtop with Opening Canvas ($10,000)
  • Hardtop with Extended Sunshade ($14,615)
  • Hardtop Opening Canvas and Extended Sunshade ($18,462)
  • Bow Shade System ($923)
  • Premiere Audio Stereo Upgrade ($2,077)
  • SmartCraft VesselView Display ($1,531)
  • Blue LED Lighting Package ($1,615)
  • Electric Grill ($2,462)
  • Air Compressor for water toy inflation ($231)
  • Bow Ladder with Hatch ($300)

The SLX 310 OB custom trailer comes standard.


Sea Ray offers a five-year factory warranty program, which Sea Ray calls “SURPA5S.” This is five years of bow-to-stern factory warranty for the boat and its components from defects in materials or workmanship. The engine is covered for the same five-year period, using a warranty backed by Mercury and Brunswick product protection. Finally, all Sea Ray sport boats have a limited Lifetime Structural Hull Warranty.



Consider the benefits of the outboard-powered bowrider over the stern-drive counterparts.

The SLX 310 OB is an entertainment-oriented bowrider, and the outboard model of Sea Ray’s SLX 310 line. There are few differences in size, so a major decision here is between the outboard engines and a sterndrive. Both have their advantages; here is a look at the pro-outboard side of the argument:

  • Outboard motors are easier to access, lower maintenance, easier to winterize, and generally easier to work on when necessary.
  • In the last five years, fiberglass outboard registrations have increased +29.8% while I/O’s have declined 18.2%.*
  • A boat equipped with an outboard is easier to repower or upgrade to more HP or newer technology. To replace an inboard/outboard motor would be much more troublesome.
  • Because the props are farther aft than they would be on a sterndrive, a higher top speed may be possible.

*source: Statistical Surveys, LLC

Most buyers looking for an entertaining boat will find little lacking in design from the SLX 310 OB.

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