LED Light Bars  /  40 Inch

40 Inch LED Light Bars

The full-width size for truck and Jeep roofs, windshield mounts, UTV roofs and boat T-tops. Single row, double row, curved and marine, with kits for trucks, Bronco and side-by-sides.

  • 52,800Raw lumens, double row
  • IP69KSealed housing
  • 12V / 24VPlug-and-play
  • LifetimeLimited Warranty
Shop 40 inch bars Kits for my vehicle
Black Oak LED 40 inch double row LED light bar with silver mounting brackets on wet gravel

Before you buy

Will it fit?Double row needs 42 in. bracket to bracket, single row 43-5/16 in. Most trucks: the roof or windshield line.Fit guideSingle or double row?Single row is slimmest. Double row puts out twice the raw lumens. Curved wraps the beam around the corners.CompareIs the wiring included?Yes. 12 ft harness, switch, relay and fuse, plus brackets and hardware.In the box
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40 Inch LED Light Bars

40 inch light bar guide

Fit, mounting and wiring for a 40 inch light bar

Everything buyers ask us before ordering a 40 inch bar, answered with the real measurements, the wiring diagram and the numbers from our spec sheets. The short version: measure the flat span, pick single row for a low profile or double row for maximum output, and everything you need to wire it is in the box.

Single, double or curved?

Single row: slim 2-9/16 in. tall housing for roof racks, windshield lines and T-tops. 200W and 26,400 raw lumens on 5W LEDs.

Double row: two rows of LEDs in a taller straight housing for the most output from one bar. 400W and 52,800 raw lumens.

Curved double row: the same 400W and 52,800 raw lumens in an arc that follows a roofline or bumper and spreads light toward the corners.

40 inch LED light bar styles compared: single row, straight double row and curved double row
Illustration. Compare exact dimensions on each product page.

Will it fit?

Measure the flat span where the bar will sit, bracket to bracket. The 40 inch single row needs 43-5/16 in., the double row needs 42 in. and the curved double row needs 42-1/8 in. On most trucks and Jeeps that is the roof or windshield line; on UTVs, the front of the roof; on boats, the T-top or hardtop. The vehicle kits below are pre-fit to their model years.

40 inch single row LED light bar dimension drawing
40" single row: 43-5/16 in. wide with brackets, 41-15/16 in. housing, 2-9/16 in. tall, 3-1/4 in. deep.
40 inch double row LED light bar dimension drawing
40" double row: 42 in. wide with brackets, 41-1/2 in. housing, 4-1/8 in. tall with bracket, 3-1/2 in. deep.
40 inch curved double row LED light bar dimension drawing
40" curved double row: 42-1/8 in. wide with brackets, 41-9/16 in. housing, 4-1/8 in. tall with bracket, 4-5/16 in. deep.

How it mounts

Every bar bolts down with the end brackets and hardware in the box. The bracket rotates so you can aim the beam after it is mounted. For tubes and rails, add a universal clamp bracket.

Roof or windshield lineThe most common 40 inch install on trucks, Jeeps and overland builds. Curved double row follows the roofline and spreads light to the sides.
Front bumperRaptor and Ram 2500 / 3500 kits put a 40 inch curved double row in the bumper using factory holes.
UTV roofPolaris General, Can-Am Maverick X3 and Yamaha YXZ kits mount a 40 inch double row across the front of the roof.
Boat T-top or hardtopMarine bars in white housing, IP69K sealed for saltwater and washdown. The single row stays low at 2-9/16 in. tall so it clears the radar.

What's in the box

Nothing else to buy for a standard install. You will need a drill, a pencil and zip ties.

  • 40 inch LED light bar with 16 in. lead and 2-pin Deutsch connector
  • 12 ft wiring harness
  • On/off switch
  • Relay and inline fuse
  • Stainless end mounting brackets
  • All mounting hardware
  • Vehicle kits add the model-specific bracket

Wiring diagram

The harness is plug-and-play: connect the red lead to the battery positive, the black to the negative, run the switch into the cab and plug the bar into the Deutsch connector. The relay keeps the full load off your switch. Single row bars use a 20A fuse; double row and curved bars use 25A.

Download the quick start guide (PDF)

Light bar wiring diagram Battery positive runs through the inline 25A fuse to the relay. The in-cab on/off switch triggers the relay, and the relay powers the light bar through the 2-pin Deutsch connector. The relay and the light bar ground to the battery negative or a clean chassis ground. GROUND: battery negative or clean chassis ground BATTERY 12V or 24V +− 25A FUSE RELAY included ON/OFF SWITCH in cab, 3/4 in. hole trigger Deutsch 2-pin 40" DOUBLE ROW Harness: 12 ft, fuse, relay and switch included Lead from bar: 16 in. to 2-pin Deutsch powergroundswitch trigger
Factory upfitter switchesWiring into a Ford, Ram or GM upfitter switch? Skip our relay and connect directly; the upfitter circuit already has one.
Keep it watertightUse heat-shrink butt connectors or solder sleeves on any splice. The Deutsch connector can be cut off if you need a custom run.
Route it cleanZip-tie the harness away from heat, sharp edges and moving parts. Mount the switch where you can reach it seated.

Brightness & beam

Figures are for our 5W LED builds, the brightest version of each bar. Combo optics put a 15° spot down the center for distance and 45° flood on the sides for width; spot and flood-only versions are available on the single row, double row and curved bars. Double row and curved bars are 6,000K, and every bar is rated for 50,000 hours.

40" double row, 400W
52,800 lm
40" curved double row, 400W
52,800 lm
40" single row, 200W
26,400 lm
LED light bar beam pattern guide comparing spot, flood and combo beam shapes
Illustrated beam shapes, not measured light output. Tap to enlarge.

40 inch light bar specs

5W LED builds. Every bar: IP69K sealed, OSRAM LEDs, Lifetime Limited Warranty. Pro Series 3.0 bars run on 12-30V DC, are rated for 50,000 hours and -40° to 145°F; double row and curved bars are 6,000K.

Every number here is the 5 Watt build. It is our highest-output version and the one we recommend. Many bars also come in a lower-priced 3 Watt build; compare both on the product page.

BarWattageRaw lumensLEDsSize with bracketsWeight
40" single row200W26,4004043-5/16 x 2-9/16 x 3-1/4 in.11.4 lb
40" double row400W52,8008042 x 4-1/8 x 3-1/2 in.13.8 lb
40" curved double row400W52,8008042-1/8 x 4-1/8 x 4-5/16 in.13.8 lb
40" marine single row200W26,4004043-5/16 x 2-9/16 x 3-1/4 in.11.4 lb
40" marine curved double row400W52,8008042-1/8 x 4-1/8 x 4-5/16 in.13.8 lb

Kits for your vehicle

Bar and bracket in one order, pre-fit to the model years listed, bolting to factory holes.

Toyota Tacoma40 inch curved kitFord F-150 Raptor40 inch curved bumper kitRam 2500 / 350040 inch curved bumper kitFord Bronco40 inch single row windshield kitPolaris General40 inch double row kitCan-Am Maverick X340 inch double row kitYamaha YXZ 1000R40 inch double row kitBoats40 inch bar and flood pod kitAny other vehicleUniversal brackets and clamps

40 inch LED light bar questions

What is the brightest 40 inch light bar Black Oak makes?

The 40 inch double row and the 40 inch curved double row are the brightest, at 400W and 52,800 raw lumens on 5W LEDs. The 40 inch single row is 200W and 26,400 raw lumens.

Will a 40 inch light bar fit my vehicle?

Measure the flat span where the bar will sit, bracket to bracket. The 40 inch single row needs 43-5/16 in., the double row needs 42 in. and the curved double row needs 42-1/8 in. On most trucks and Jeeps that is the roof or windshield line; on UTVs, the front of the roof; on boats, the T-top or hardtop. The vehicle kits below are pre-fit to their model years.

Single row or double row?

Single row when height is the constraint (behind a grille, on a roof rack, under a boat T-top) or when you want the slimmest look. Double row when the position has room and you want the most output from one bar, twice the raw lumens of the single row. Curved double row when the bar sits on a bumper or roofline and you want the beam to wrap the corners.

Does a 40 inch light bar come with a wiring harness and switch?

Yes. Every 40 inch bar ships with a 12 foot harness that includes the on/off switch, relay and inline fuse, plus stainless brackets and mounting hardware. It plugs into the bar's 2-pin Deutsch connector and runs on 12V and 24V systems.

What is the difference between the marine and standard 40 inch bars?

Same LEDs and optics. The marine bars use a white powder-coated housing and are sold with marine mounting options; every bar is IP69K sealed for saltwater and pressure washdown.

What warranty comes with a 40 inch light bar?

Every 40 inch Black Oak LED light bar in this collection is covered by a Lifetime Limited Warranty. See each product page for the terms.

Other sizes: 30 inch light bars, 50 inch light bars, or every size and type in LED light bars. Designed and engineered in Sarasota, Florida.