Help Center


What’s the difference between an acrylic and polycarbonate lens?
Given its weather resistance and clarity, acrylic has long been the most widely used material for lenses. However, polycarbonate is much less likely to shatter, chip or crack upon impact and can withstand higher exposure to heat...
Are your LED lights polarity-sensitive?
By nature, LED lights are polarity-sensitive. If the voltage is of the wrong polarity, it is said to be reverse-biased. Very little current will flow, and the device will not light up. Truck-Lite has developed LED lights that are not polarity...
Is there a Lifetime Warranty on LED lighting?
Truck-Lite offers a variety of warranties, depending on the product. Products that qualify for our limited lifetime warranty show the following symbol:  To learn more about our warranty programs, visit the warranty page.
Where can I buy Truck-Lite product?
Great question! Visit our distributor search to locate a dealer near you.
What does FMVSS-108 stand for?
In the United States, the Federal Motor Vehicle Safety Standards No. 108 (FMVSS-108) is the federal regulation that defines the use of exterior lighting products. It is over 168 pages long and includes a number of written interpretations...
Why are my lights cracking?
Most lights are made from polycarbonate which is the toughest, highest melting plastic generally available. However, it can be attacked (which causes cracking) by some chemicals or cleaners. The answer is to avoid incompatible cleaners and/or to use ...
Are clear lenses legal on rear stop/turn/tail lights?
Yes. The Federal Motor Vehicle Safety Standards clearly state that measuring the performance and color of a lamp assembly is done with the light source energized.  There is nothing illegal or non-compliant about red or yellow LEDs behind...
What is the difference between FMVSS: PC and FMVSS: P2?
P2 is the minimum standard for clearance, side marker, and identification lights. All Truck-Lite lights meet this standard, even if they are marked PC, P3, etc. PC lights are to be used as a combination light, meaning the light should be mounted on ...
I’m painting my vehicle. Do I need to worry whether or not a little bit of paint gets on the lights?
You should be careful to avoid getting paint on the lights; most paints (excluding water based) are incompatible with polycarbonate lights. They may also cause wires or cable insulation to crack.
The lenses on my customer’s lamps are hazing and cracking. What’s the deal?
Hazing and cracking are almost always caused by incompatible chemicals or cleaners. Although polycarbonate lenses are generally very durable, they can crack due to the combination of stress induced by the molding process combined with accelerated...
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Why can't I place marker lamps at the bottom of my trailer?
How can I spot non-compliant products?
As you are likely aware, the three marker lamps at the top-rear of the trailer, mounted around the center line of the vehicle, are called "identification lights." Their purpose is to alert following drivers that the vehicle with these lights is a commercial...
What affects the lifespan of LEDs?
Efficient design of the circuit is the key to ensuring that the LED lamp assembly will be robust and last for a long time.  One key factor is to ensure that the discrete LEDs are operated below their maximum rating.   The Truck-Lite Engineering...
Is the lifespan reduced if the LEDs are frequently turned on and off?
No. In fact, at Truck-Lite’s R&D lab, the original prototype LED stop/turn/tail light has been blinking since 1998!
What is the lifespan of LED lighting?
As you may know, LED lights are monochromatic.  Monochromatic means that red LEDs only produce red light, amber LEDs only produce amber light... but now there are white LEDs. White light is often produced by using a blue LED covered by a ceramic...
Can I still drive a vehicle with LED lights if some of the LEDs go out?
This is open to interpretation. It is generally assumed that, if several diodes fail on a light, but most of the light remains lit, you are okay to drive the vehicle. Truck-Lite strongly recommends replacing lights with failed diodes as soon as possible...
Do the TOP markings really need to be at the top?
Yes, it is an obligation for legal compliance.
My customer wants to add some auxiliary lights (i.e. Illuminated signs, deceleration lights, decorative lights). Are these legal?
Yes, provided they do not render inoperative any device in compliance with FMVSS-108, negatively affect the performance of required equipment or create confusion or misunderstanding of lighting signals. Feel free to contact Truck-Lite if you have...
My customer wants to use a light for a side turn that isn’t listed for that function. Is this OK, seeing as how side turns aren’t required anyway?
Be careful that it doesn’t violate some state laws regarding color or location. If it is also used as a side marker, the function must be listed on the lens code.
FMVSS-108 says that some lights must be mounted “as high as practicable.” What is practicable?
NHTSA has stated that the vehicle manufacturer has the responsibility to choose the best mounting location “in light of the particular design/configuration of the vehicle involved” and they will not contest it unless it is “clearly erroneous.” Recently...
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Are heavy-duty harnesses worth the extra cost?
We think so! Heavy-duty harnesses provide an independent (secure) ground and less voltage drop, and are completely sealed to avoid corrosion. We don't recommend taking any chances when it comes to safety and efficiency.
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Other Products
Can I remove the reflectors on my trailer?
No, reflectors are a legal requirement. Placed as far apart as practicable, they indicate the trailer's presence and width/length to other vehicles on the road.
Can I add extra lights to my truck, tractor, trailer, or body over and beyond the legal requirements in FMVSS 108?
Lighting that goes beyond the legal requirements of FMVSS 108 is called auxiliary lighting. Auxiliary lighting can be added to the vehicle as long as it does not cause confusion or impair the effectiveness of any of the required lights.
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