Taillights cloudy (never)?

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Goofy question: Why is that it only seems like headlights turn cloudy with oxidation but I have never seen taillights do this? Aren't both polycarbonate plastic lens?
 
I'm pretty sure both are the same. Headlights get exposed directly to dust and debris unlike tail lights.
 
Originally Posted by WhizkidTN
Goofy question: Why is that it only seems like headlights turn cloudy with oxidation but I have never seen taillights do this? Aren't both polycarbonate plastic lens?

Having seen many smashed and crumbled tail lights, I am certain they are acrylic. Acrylics are much more UV-resistant compared to polycarbonate.
 
Originally Posted by vavavroom
Originally Posted by WhizkidTN
Goofy question: Why is that it only seems like headlights turn cloudy with oxidation but I have never seen taillights do this? Aren't both polycarbonate plastic lens?

Having seen many smashed and crumbled tail lights, I am certain they are acrylic. Acrylics are much more UV-resistant compared to polycarbonate.


Agreed. Although the driver's side tail light on my Sedona has the slightest haze on it. Not sure why. The clearcoat and paint is pretty crap on this van. Maybe their plastics aren't the best either. I know some of the interior plastic bits are the most brittle I've seen. Still has been a great vehicle.
 
Acrylics are very stable and don't degrade or even fade much over several decades. I presume that clear tail light lenses are made from polycarbonate. So they should degrade over time. Another advantage of acrylics is that you can make a tail light lens that has integrated reflectors and intricate diffusers. Interior plastics contain plasticisers that gas out over time, causing the material to shrink and to get brittle, and to fade, The process accelerates with exposure to UV light.
 
Originally Posted by PimTac
Headlights get exposed directly to dust and debris unlike tail lights.


the headlamps get "sandblasted" by dust and debris in the air while moving forward at speed..
most people aren't driving thousands of miles at speed, in reverse...
 
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My body shop friend said a long time ago that the driver's side of a vehicle takes more beating from the elements than does the passenger side.

His reasoning is that there is more debris (dirt and road chemicals) built up near the center of the road because of the crown and sloping.

Suppose he was referring to two lane highways, which we all travel on a lot in our area.
 
This is a great question ðŸ‘ðŸ». I wonder if the color of the rear lights has any effect. Or maybe the color hides the yellowing well?
 
Originally Posted by vavavroom
Acrylics are very stable and don't degrade or even fade much over several decades. I presume that clear tail light lenses are made from polycarbonate. So they should degrade over time. Another advantage of acrylics is that you can make a tail light lens that has integrated reflectors and intricate diffusers. Interior plastics contain plasticisers that gas out over time, causing the material to shrink and to get brittle, and to fade, The process accelerates with exposure to UV light.

Spot on. Both headlight and taillight lenses can fade, yellow, and/or deteriorate from UV damage more than anything else.

A good UV protection sealant wax can help avoid the problem. I've seen numerous 2-year-old and older vehicles with yellowing (plastic) headlight lens covers. UV can be brutal, which is why exterior paint finishes have had clear-coat on them for many years - UV protection.

With some simple occasional UV protection care...even a 6-year old car (or older) can have their plastic lens covers look like new without having to do any kind of restoration at all.

[Linked Image]
 
This is a great question. I wondered this too.

Originally Posted by HYUNDAIFAN0001

With some simple occasional UV protection care...even a 6-year old car (or older) can have their plastic lens covers look like new without having to do any kind of restoration at all.

What is your recipe for simple UV protection care, esp for the lights?
I was told to you Meguair's PlastX but I have no idea if it needs any prep before using it.
 
*Between the heat of the head lamps themselves, most bulbs still being halogen even today.
*DRLs, meaning that some lights are on more often than not even at a lower wattage.
*The wind buffeting at highway speeds.
*Along with harsh sunlight & road debris/sand/dirt.
It's no wonder that these acrylic lenses fog in no time at all. Then, depending on where one lives(climate) is how quickly they'll fog/haze.
 
Originally Posted by MoneyJohn
This is a great question. I wondered this too.

Originally Posted by HYUNDAIFAN0001

With some simple occasional UV protection care...even a 6-year old car (or older) can have their plastic lens covers look like new without having to do any kind of restoration at all.

What is your recipe for simple UV protection care, esp for the lights?
I was told to you Meguair's PlastX but I have no idea if it needs any prep before using it.

PlastX does not make mention of any UV protection, rather, its designed to clean up the lens and polish the surface.

UV protection spray waxes can do the job (most last about 6-8 weeks), while regular liquid or paste waxes with stated UV protection offer better longevity (4-6 months).

These are just a few of the many spray and regular waxes with UV protection:

Spray:
Meguiar's Gold Class Premium Quick Wax
Chemical Guys Hybrid V7
Griot's Garage Spray-on Wax
Optimum Spray Wax
303 Spray Wax & Quick Detailer
CarGuys Hybrid Wax Sealant
McKee's 37 Fast Wax
Chemical Guys Blazin' Banana Spray Wax

Regular:
Meguiar's Ultimate Liquid Wax
Chemical Guys Butter Wet Wax
Aero Cosmetics Wash Wax All Wet
P21S Carnauba Wax
Car Guys Premium Liquid Wax
Meguiar's NXT Generation Tech Wax
Collinite No. 845 Liquid Insulator Wax.
 
Any sealant with us protection capabilities can help preserve headlights and tail lights from uv damage. For physical damage protection of the headlights a protective film as in a 3M product for example can help in that regard.

There are coatings as well but the costs are higher as one might expect.
 
Originally Posted by PimTac
Any sealant with UV protection capabilities can help preserve headlights and tail lights from uv damage. For physical damage protection of the headlights a protective film as in a 3M product for example can help in that regard.

There are coatings as well but the costs are higher as one might expect.

Agree.
 
Originally Posted by Smokescreen
Tail lights aren't usually clear either so its hard to tell if they are oxidizing or not while shining the LED or paltry 5W of light through them.

Valid point - so it just pays to treat them periodically as well. Some actually have lenses with red and other colors as well.
 
I would hazard a guess that road grit and wind abrasion plus high intensity light are the main culprits for headlight lens wear, taillights are ~5watts most of the time, max 21w for brake.

Funny though, there were a few years when certain Honda and Lexus red tail lenses faded to pink very quickly. I believe there was an SB on early S2000's for the issue.
 
Originally Posted by wings&wheels
I would hazard a guess that road grit and wind abrasion plus high intensity light are the main culprits for headlight lens wear, taillights are ~5watts most of the time, max 21w for brake.

Funny though, there were a few years when certain Honda and Lexus red tail lenses faded to pink very quickly. I believe there was an SB on early S2000's for the issue.

Sitting out in the sun (UV) causes significant damage to anything plastic on a vehicle over time.
 
These are all good comments! I started looking at other cars on the road and noticed the same thing to about the same degree as my daughters car.

I have a 2005 Toyota Matrix XR I'm reconditioning for sale for my daughter that has had the classic issues with the headlights (which I just restored) but the taillights (which are also clear) are perfect. This car has never been detailed (to my knowledge) and certainly not in the 8+ years we've owned it. It also sits outside a good bit. I have over the years used Meguairs Lens Protector (UV blocker, not PlasticX) on the headlights but I don't think I ever put that on the taillights.

Start looking at cars on the road, parking lot, etc. and comment on what you see but it sure "seems like" my original comment is a common observation.
 
Originally Posted by WhizkidTN
These are all good comments! I started looking at other cars on the road and noticed the same thing to about the same degree as my daughters car.

I have a 2005 Toyota Matrix XR I'm reconditioning for sale for my daughter that has had the classic issues with the headlights (which I just restored) but the taillights (which are also clear) are perfect. This car has never been detailed (to my knowledge) and certainly not in the 8+ years we've owned it. It also sits outside a good bit. I have over the years used Meguairs Lens Protector (UV blocker, not PlasticX) on the headlights but I don't think I ever put that on the taillights.

Start looking at cars on the road, parking lot, etc. and comment on what you see but it sure "seems like" my original comment is a common observation.

Congrats on our restore work.

Over time...I've seen other vehicles where there is actually "peeling" on taillight plastic caused by UV damage. It depends, of course, on how much exposure, for how long, and if anything was done to provide protection. When our vehicles get detailed - everything on the exterior gets some form of protective treatment periodically...so we've never had yellowing headlight lens covers or anythings else on the exteriors fade, crack, or peel. For many years, many good products with UV protection are no big deal to include all exterior parts for protective treatment. A few are more difficult to apply or leave white residue on dark plastic trim (like NuFinish), but many others are just fine.

The Mrs Honda Accord photo (2013) demonstrates they can loo like new a long time if taken care of with some kind of viable product. My previous vehicle was an 18-year-old car with crystal clear lens covers as well.
 
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