This is my buying guide on the best 9004 LED headlight bulbs in 2023. Below is a quick summary of my top recommendations. Scroll further down to read my in depth, hands on reviews for each 9004 bulb. I’ve included photos and test results below.

BRIGHTEST BUDGET

Fahren Forscher 9004 LED Headlight Bulbs

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• Simple installation 
• Easy to aim 
• Great brightness 
• Improved visibility 
• Clean cut-off point 
• Adjustable collar 
• 14,000 lumens per set
• Up to 2,390 lux 
• 50,000-hour lifespan
• 70 watts per pair 
• 12,000 RPM cooling fan
• 89% heat retention
• 1-year warranty
• 6,500K cool white 
• IP68 rating

Overall Brightest

Auxito 2023 Upgraded 9004 LED Headlight Bulbs

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• Easy installation 
• Easy adjustable beam 
• 360° adjustable collar 
• Excellent visibility
• Fantastic heat retention of 82%
• 20,000 lumens per set
• Up to 3,160 Lux 
• 50,000-hour lifespan
• 100 watts per pair 
• 12,000 RPM cooling fan
• 82% heat retention
• Anti-static gloves for installation
• 6,000K clear white 
• IP67 rating
• 2-year warranty

WORTHY CONTENDER

Novsight 9004 N30 LED Headlight Bulbs

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• Easy installation 
• All-in-one unit 
• Full metal build 
• 13,000 lumens per set
• Great visibility 
• Satin finish
• Up to 2,340 Lux 
• 100,000-hour lifespan 
• Excellent cooling at only 121°F
• 6,500K clear white
• 60 watts per pair 
• IP68 rating

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Dual headlights are commonly replaced with a 9004 bulb. 

There are loads of 9004 bulbs on the market, which means you end up spoiled for choice. With so much variety, how are you supposed to choose the right one? 

The good news is you have me to back you up. I live, breathe, and sweat cars, so I know precisely what you should look for. 

I spent hours testing ten popular 9004 LED headlights and found the brightest three. 

The Auxito 9004 was the brightest set of LED headlight bulbs out of the lot. The reason? 

Impeccable brightness and heat retention and easy installation. 

I’ll follow that with a budget option and a runner-up for brightest.

Let’s take a closer look at the brightest 9004 LED headlight bulbs.

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IMPORTANT! – Make sure you have the correct bulb sizing and fitment so you don’t waste your money, use this handy tool to double check.

Auxito Upgraded 9004 LED Headlight Bulbs

OVERALL BRIGHTEST

Brightest of Them All

So what’s making me gush over the Auxito 2023 9004 LED headlight bulbs as the torchbearer for brightness? The manufacturers claim an astounding 20,000 lumens per pair, and in my personal experience, I witnessed them peaking above 3,000 lux – talk about being super bright!

My Testing Methodology

The process of testing remains constant. I place the bulbs 20 feet away from my lux meter, which enables me to measure the brightness and beam pattern.

I’m drawing a comparison here between the Auxito 2003 9004 LED bulbs and stock halogens. Your typical halogen bulb will churn out 725 lux in the projector test, and 910 lux in the reflector test.

During the projector test, the Auxito 2003 9004 LEDs clocked an initial score of 1,573 lux, a massive 848 lux increase compared to halogen bulbs. 

A subsequent reading taken after an average US commute time of 27 minutes, revealed that they retained a commendable 82% brightness at 1,290 lux, surpassing the average of 77%.

The reflector test had the Auxito 2023 9004 LED bulbs kicking off with an impressive 3,160 lux (a whopping 2,250 lux more than halogens). We’re talking about a staggering 350% brightness boost – truly spectacular results.

After 27 minutes, these bulbs maintained their 82% brightness retention with a score of 2,591 lux.

What struck me was the exceptional control over brightness and direction of light, especially given the high lux readings. The usually problematic lower center area was nicely illuminated, boasting a clear cut-off.

Since the cut-off is higher than usual, it’s crucial to align the lights correctly to prevent dazzling oncoming drivers. 

While the bulbs are advertised as 50 watts each, I recorded 42.4 watts during my test.

Color Temperature 

The AUXITO 9004 lights boast 6000 Kelvins, translating to a cool white for enhanced clarity.

My preference for LEDs stems from the fact that stock halogens generally produce a yellowish light with a color temperature of 3,000K. The white hue of the LEDs brings objects in front of my car into sharper focus, making me feel more secure when I’m behind the wheel.

Managing the Heat

The Auxito 2023 9004 LED bulbs incorporate a dual cooling system, feature a double-sided copper board, and are encased in an aviation-grade aluminum body. They also come with a built-in 12,000 RPM high-speed cooling fan.

Disappointingly, none of these features seem to be effective in heat management. My temperature tests revealed a staggering 219°F for the main unit and 154°F for the driver after 27 minutes.

These temperatures are excessively high, and I’m skeptical about the bulbs’ ability to last the advertised 50,000 hours.

Noteworthy Features 

The 9004 LED headlight bulbs come with a 360-degree adjustable collar. I appreciated the thoughtful gesture from Auxito to provide antistatic gloves to protect my hands during installation.

Auxito deploys intelligent CSP chips affixed to an ultra-thin 0.039 inch baseboard to maximize brightness and enhance nighttime visibility. This was substantiated in my test results.

Installation

The straightforward yet compact design is perfect for installation. It took me less than ten minutes, courtesy of the 1:1 halogen plug-and-play design. Aligning the beam was just as simple.

Durability and Longevity

The AUXITO 9004 comes with an IP67 rating for waterproofing. I braved a heavy storm for nearly an hour and the bulbs stood their ground, showing no signs of trouble.

Auxito promises a lifespan of 50,000 hours, but considering the high temperatures, I doubt they’ll hit that mark. However, they should deliver a solid performance for at least the duration of the 2-year warranty.

Feedback from Other Drivers

The AUXITO 9004 LED headlight bulbs have garnered over 2,000 customer reviews with an average rating of 4.4/5 stars. 

Users have applauded the bulbs for their easy installation and enhanced brightness during nighttime drives. 

The primary downside noted by users is the bulbs’ tendency to overheat, which is something I experienced as well.

The Final Verdict

The Auxito 2023 9004 LED headlight bulbs earn my vote as the brightest bulbs; with a 350% brightness improvement over halogens, it’s hard to find anything that can hold a candle to these.

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Top Pick for the Budget Conscious

Just because you’re mindful of your budget doesn’t mean you have to settle for less, and the Fahren Forscher 9004 LED headlight bulbs are a testament to that. The manufacturers have pegged them at 14,000 lumens per pair, and they hit as high as 2,390 lux, promising enhanced brightness. The only thing that’s budget-friendly about them is their price tag.

My Trial Run

In my projector test, these bulbs clocked in at an initial 1,472 lux, which is roughly double what you’d get from stock halogen bulbs. After the usual 27-minute test period, they retained a whopping 89% brightness, delivering 1,313 lux. This result was well above average, showcasing remarkable heat retention.

During the reflector test, the Fahren Forscher 9004 LEDs registered an initial 2,390 lux, a significant 1,480 lux jump over stock halogen bulbs, equating to around 250% extra brightness. After the 27 minutes, they held steady, maintaining the 89% brightness level at 2,137 lux.

The tests also revealed a decent cut-off point in line with standard headlight expectations. There was excellent command over the brightness, with only the usual suspects – the top and bottom center – being slightly weak spots.

I was quite impressed with the superb light control and a well-balanced distribution between the left and right sides. The clean cut-off also ensured that there was barely any scattering of light.

Interestingly, after 27 minutes, my tests showed that the bulbs hit 25.9 watts, a fair bit short of the advertised 35 watts. 

Color Temperature 

These headlight bulbs sport a cool white color at 6500 Kelvins. When I took them for a spin, I was pleasantly surprised by the stark clarity of road signs in comparison to the usual halogens.

Keeping the Heat in Check

These bulbs are constructed from aviation-grade aluminum and feature a unique hollow-carved heatsink design. They also boast a built-in 12,000 RPM turbofan. My tests showed that the main unit reached temperatures of 185°F, while the driver warmed up to 120°F.

While these temperatures aren’t as high as the Auxito 2023 9004s, they’re still a tad hotter than I’d prefer. This makes me question the claimed longevity of 50,000 hours.

There’s another quirk about the fan: it gets seriously loud. While this may not be an issue for some, I found it increasingly noticeable and mildly distracting over time.

Handy Extras 

I found it neat how all Fahren bulbs come packaged in a small black bag. It felt like unboxing a surprise gift. Inside, you’ll find a detailed manual, which honestly, wasn’t required as the bulbs were a breeze to install. In addition, there’s double-sided tape, a tiny aluminum wrench for the adjustable collar, and four zip ties.

What sets Fahren apart is the inclusion of two extra gaskets – a thoughtful touch.

Installation

Thanks to the plug-and-play design, I breezed through the installation process, wrapping it up in about five minutes. Adjusting the beam was a similarly quick affair.

Durability and Longevity

The Fahren Forscher 9004 LED headlight bulbs come with an IP68 rating, signifying their waterproof, dustproof, and generally weather-resistant characteristics. This is the best possible rating, and it definitely bolstered my confidence during my drives in the rain.

They claim a lifespan of 50,000 hours and Fahren offers a 1-year warranty.

Feedback from Fellow Drivers

The Fahren Forscher LED headlight bulbs have raked in over 59,000 customer reviews, boasting an average rating of 4.5/5 stars.

Users have heaped praises on the ease of installation and the efficacy of the lights.

The noisy fan has been a common point of complaint among drivers, so it seems I’m not the only one irked by it.

In Conclusion

With their affordable price and exceptional performance, these lights certainly make for an attractive option. They rank highly among the brightest 9004 bulbs for budget-conscious drivers. With these installed, you can expect clear visibility and more confident driving after dark.

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Strong Second Option

The Novsight 9004 LED headlight bulbs are undoubtedly a strong second place contender. Boasting over 2,000 lux, they exhibit brilliant light retention and are marketed at 13,000 lumens per pair. To top it all off, they come with some handy freebies.

My Testing Journey

In my projector test, the Novsight 9004 LEDs came in with an initial rating of 1,320 lux, a good 595 lux above the standard halogen bulbs.

After 27 minutes, they slipped to 77% brightness, which is about par for the course.

As for my reflector test, it revealed an initial rating of 2,340 lux, a hefty 1,430 lux more than stock halogens, making them a solid 250% brighter than standard bulbs.

After the usual 27-minute period, they held on to 77% brightness, translating to 1,801 lux.

The test also showed a decent cut-off point, even on the top and bottom, which is quite a rare find. The typical weak spot was well addressed, leading to minimal scattering and fantastic overall light control.

The bulbs are advertised at 60 watts per set, but my readings showed each bulb clocked in at 25.1 watts.

Color Temperature 

The bulbs give off a pleasant and sharp cool white light, measured at 6,500 Kelvins. I really enjoyed hitting the road with these bulbs installed; I could discern objects on the road faster and more clearly than with the factory bulbs.

Handling the Heat

I’m usually skeptical about all-in-one units due to their tendency to heat up rather quickly. The Novsight 9004 LED bulbs, however, are a pleasant exception. The integrated silent turbofan and the aviation aluminum material seem to do a stellar job at heat management.

My tests showed that the unit reached a relatively cool 121°F after 27 minutes. And true to the claim, the fan was indeed silent, unlike the Fahren Forschers.

Handy Extras 

One of the standout aspects of these bulbs is their unique all-in-one design, with an integrated driver and an entirely metal construction – no plastic parts to be seen. This makes for a solid and sturdy bulb, made even more appealing with a satin finish.

To sweeten the deal, the Novsight 9004 LED headlights come with gifts, including a textile keychain and a Novsight-branded nano traceless magic sticker – nifty little additions.

Installation

Installation was a breeze, thanks to the 1:1 halogen plug-and-play design, a perk of the all-in-one structure. It took me less than ten minutes to get it done. Aiming the beam was equally easy, and I highly recommend doing this to avoid blinding other drivers.

Durability and Longevity

These headlight bulbs boast an IP68 rating, which implies they’re weatherproof and dust-resistant. They’re touted to have a staggering estimated lifespan of 100,000 hours, which significantly outstrips the average. However, I remain skeptical about this claim.

Feedback from the Road

The Novsight 9004 LED headlight bulbs currently hold a 4.6/5 star rating.

Drivers have particularly lauded the compact and robust build of these headlight bulbs, as well as the impressive brightness they offer.

The main complaints appear to center around their unsuitability for DRL use.

Final Thoughts

The Novsight 9004 LED bulbs clinch the runner-up spot in my book. They may not quite match up to the brightness of the Auxito 2023 9004s or their superior heat retention, but they’re more affordable and manage to stay impressively cool.

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Important Considerations When Buying 9004 LED Headlight Bulbs

9004 bulbs aren’t for every vehicle. I know for a fact that they’re popular replacements for most VW vehicles and some Toyotas. It’s vital to check the vehicle’s user manual to determine if they’re suitable for others.

The other thing to keep in mind about 9004 bulbs is that they’re dual-beam, so they only fit in vehicles with two headlights. If the car has four headlights, it needs a different bulb for high and low beams, so the 9004 isn’t suitable.

Some drivers attempt to swap the 9004 for the 9007, which can be done if the socket is correct. The difference between the two is that the 9004 has a ground pin on one side and the high/low pins in the middle, while the 9007 has its ground pin in the middle and high/low positive pins on the outside.