2022 International LT Bulb Sizes (Headlight, Tail, Fog)

As an ASE-certified master technician who has spent countless hours working on heavy-duty commercial trucks, I know how critical proper lighting is for a 2022 International LT. Whether you’re an owner-operator or managing a fleet, keeping your rig’s lights functioning perfectly is a matter of DOT compliance and safety. The 2022 International LT is offered with both standard halogen setups for fleet applications and premium full-LED assemblies for higher trims or specific orders.

Below is a comprehensive guide to the bulb sizes for your 2022 International LT, along with upgrade advice, replacement tips, and common issues to watch out for.

Quick reference

Note: Many 2022 International LT models come equipped with sealed LED assemblies from the factory (especially for headlights, taillights, and cab markers). If your truck has factory LEDs, the entire housing or module must be replaced if it fails. The sizes below apply to trucks equipped with replaceable incandescent/halogen bulbs.

LED vs halogen upgrade considerations

Upgrading a commercial truck like the International LT from halogen to LED bulbs provides massive benefits in nighttime visibility, reduced eye strain, and lower power draw. However, heavy-duty electrical systems can be sensitive to aftermarket modifications.

• CANBUS Errors and Flickering: The LT’s body control module (BCM) monitors circuits for burned-out bulbs to alert the driver. Because LEDs draw significantly less power than halogens, the BCM may think the bulb is dead, causing dashboard warnings or rapid flashing (hyper-flashing) of turn signals. Always choose CANBUS-ready LED bulbs or install load resistors for the turn signals and headlights.
• Beam Pattern: The halogen headlight housings on the LT use reflector or projector lenses designed for a 360-degree light source. When upgrading to H11 or 9005 LEDs, ensure you buy bulbs with highly adjustable collars so you can orient the LED chips perfectly horizontally (at 3 and 9 o'clock). This prevents blinding oncoming drivers and gives a sharp cutoff line.
• Space and Adapters: Heavy-duty headlight housings can be tight. Make sure the LED bulbs you select have a compact cooling fan or heatsink that will clear the dust covers on the back of the headlight assembly.

How to replace each bulb

• Headlight Low/High Beams: Accessing the headlights on the International LT requires tilting the hood forward. The back of the headlight assemblies are easily accessible from inside the wheel well/engine bay area. Twist off the protective dust cover, unclip the wiring harness, and twist the H11 or 9005 bulb counterclockwise to remove it.
• Fog Lights: Fog lights are mounted lower on the bumper. Depending on the bumper configuration (aero vs. standard), you may need to remove an access panel or simply reach up behind the bumper. Twist the bulb counterclockwise to pull it out.
• Front Turn Signals / DRLs: Located within the main headlight housing on most trims. Once the hood is tilted, reach the upper or outer edge of the back of the housing. Twist the socket out and pull the 3157 bulb straight out of its base.
• Rear Lighting (Brake, Turn, Tail, Reverse): Commercial trucks use standard DOT-compliant rear light boxes or mudflap hangers. If you have replaceable bulbs, simply remove the screws holding the red/clear lens in place and swap the bulb. Most modern LTs, however, use sealed 4-inch round or oval LED pods. For these, use a flathead screwdriver to pry the rubber grommet loose, disconnect the 3-prong pigtail, and push a new sealed LED pod in.
• Cab Markers / Side Markers: Many of these are sealed LED units on the 2022 LT. If a bulb goes out, you generally have to unscrew the entire amber or red marker assembly, unplug it from the harness, and replace the whole piece.
• Dome/Map Lights: Use a plastic trim tool to gently pop off the clear plastic lenses inside the cab overhead console. Swap out the 194 or festoon (211-2) bulbs, but make sure the switch is off—these bulbs get hot quickly!

Common lighting issues for this generation

The 2022 International LT is a robust truck, but fleet operations take a toll on lighting components.

One of the most common issues is corrosion in the rear pigtail connectors. Winter road salt and magnesium chloride can eat into the 3-prong plugs at the rear tail lights, causing intermittent brake or turn signal failures. Using dielectric grease on all exterior bulb connections is highly recommended for preventative maintenance.

Another frequent issue is standard halogen bulbs vibrating to death. The heavy diesel vibration and rough highways can cause halogen filaments to break prematurely. Upgrading to quality LEDs or reinforced "Long Life" (LL) halogens is a smart move for owner-operators tired of frequent replacements. Lastly, if you have factory LED headlights, watch for moisture intrusion; a cracked lens usually means the entire expensive module needs replacement.

If you are dealing with persistent electrical faults, short circuits, or BCM issues that a simple bulb swap won't fix, don't leave it to chance. Find a trusted shop on Repairius.