The Comprehensive Guide to Peterbilt 389 Headlight Options

The Comprehensive Guide to Peterbilt 389 Headlight Options - by BTS Lighting

Why Are Peterbilt 389 Factory Headlights So Dim?
If you’ve ever found yourself struggling to see the road at night in your Peterbilt 389, you’re not alone. The stock projector headlights have several design flaws that impact performance:

Underpowered Halogen Bulbs – The factory H11 halogen low beams produce only ~130 lux, which is barely adequate for night driving. High beams are better at 656 lux, but still far from modern lighting standards.
Dust & Moisture Intrusion – The headlight housings often accumulate dust and condensation over time. Many LED conversion kits don’t include proper dust covers, leaving the headlight vulnerable to dirt and debris.
Poor Beam Projection – The projector lens design is flawed, leading to scattered, weak light output even with upgraded halogen bulbs.
The solution? A properly engineered LED headlight upgrade that fixes these flaws while ensuring a fully sealed installation.

Beam Pattern Testing: Comparing Headlight Options
To provide real-world performance data, we tested multiple Peterbilt 389 headlight options using a digital lux meter and beam pattern analysis, measuring 25' from a wall. Lumens are the amount of light a light source emits, whereas lux is the amount of light that actually gets projected onto the road (or wall in our testing). Each headlight was warmed up for 10 minutes before taking measurements to ensure accurate results.


1. OEM Halogen (Stock Headlights) – The Baseline
OEM Halogen
Low Beam Output: 130 lux
High Beam Output: 656 lux
Beam Pattern: Weak central hotspot, uneven spread
The factory halogen headlights provide subpar performance. Low beams lack reach, and high beams are just barely adequate. Most 389 drivers upgrade immediately after experiencing stock headlights.


2. United Pacific Halogen – A Step Up
United Pacific Halogen
Low Beam Output: 360 lux
High Beam Output: 755 lux
Beam Pattern: Improved brightness, similar focus
If you want to stick with halogens, United Pacific’s version offers noticeable brightness improvements. However, it still falls short of LED technology.


3. United Pacific Reflector LED – Bright but Uneven
United Pacific Reflector LED
Low Beam Output: 602 lux
High Beam Output: 1,900 lux
Beam Pattern: Bright but uneven, with noticeable dips at the edges
While one of the brightest options tested, the beam pattern has inconsistencies that could impact visibility for oncoming traffic.


4. United Pacific Jewel Eye LED – Wide Beam, Limited Intensity
United Pacific Jewel Eye LED
Low Beam Output: 340 lux
High Beam Output: 745 lux
Beam Pattern: Wide but lacking intensity beyond central hotspot
While it offers a broad beam, the overall intensity is underwhelming, making it only slightly better than OEM halogens.


5. United Pacific Projector LED – The Budget Pick
United Pacific Projector LED
Low Beam Output: 320 lux
High Beam Output: 720 lux
Beam Pattern: Balanced, but not exceptionally bright
A good entry-level LED option, but better alternatives exist for those seeking maximum performance.


6. JW Speaker 9600 Heated LED – The Premium Pick
JW Speaker 9600 Heated
Low Beam Output: 556 lux
High Beam Output: 815 lux
Beam Pattern: Excellent down-road illumination
A top-tier LED solution built for cold climates, with heated lenses to prevent ice buildup.


7. Bonus Test: Halogen Headlight with Alpha Series LED Bulbs
Alpha Series LED in Halogen Housing
Low Beam Output: 770 lux
High Beam Output: 2,180 lux
Beam Pattern: Best combination of brightness & focus

This hybrid setup delivered the highest performance, maintaining an OEM-like beam pattern while dramatically increasing brightness.