Highway sandblasting, pitting, scratching will damage the lens surface but none of these things will turn a lens yellow.
Two things cause a lens to yellow
1. Most common is oxidation.
There is virtually no damage caused by oxidation.
2. Ultra Violet rays. Your protective UV layer shields against this type of yellowing.
It can be scratched and pitted but it will still protect the lens from UV yellowing.
Once removed there is nothing to stop the lens from UV damage. This damage cannot be sanded away. People who think a scratched UV layer should be removed are in error. Scratches do not stop light from passing through the lens.
A mildly scratched or pitted lens can still project light. A yellow lens defuses and blocks the light. Oxidation is reoccurring but it can be removed.
Once your lens yellows from UV light it will stay yellow. It's up to the reader to discern factual information from assumptions. Are you concerned about a few scratches on your headlight or light projection? If its scratches than sand away! If its light projection: Stay away from abrasives of any kind.
While it is true that abrasives will ruin plastic lenses they are already ruined anyway by the "sandblasting" you receive driving down the road on a daily basis.I use a combination of comet cleanser and water. It removes most (not all) but most of the oxidation and polish lightly with a little rain dance polish. The lenses clean up quite nicely and do not yellow.
They just get messed up again 3 or 4 months later and I just do them again...cheap. None of those so called kits do anything what so ever except take your money and then come up with every reason in the world not to refund it when you complain..."I mean really, you didn't follow the directions". The products don't work and that is all there is to it. People would not complain to sites like these if the products worked. The few pluses you see here are all written by the companies that make the products!
My headlights were actually brown. They were like that when I bought the car. I was looking to replace them when a friend of mine bet me $20.00 he could make them look like new in less than five minutes.
I figure it was a sucker bet and I took him up on it. I lost!
I had not heard about Pittman 360ID. I thought the lens was beyond repair. Pittman's works and it works fast. It cost me twenty dollars to find out about Pittman's but I saved a few hundred dollars because now I don't have to replace the lens. The lens are crystal clear now, I would not have believed it if I had not seen it.
Plastic headlights damage very easily. What works on glass will destroy plastic.
Don't use any solution that involves abrasives, like rubbing compound and sandpaper.
Two things not to do to plastic, Use an abrasive on it or Pam. If your headlights are already damaged, you don't have much to lose. If your headlights are relatively new you can do a lot of surface damage oven cleaners and abrasive cleaners.
Most stores still push abrasive cleaning kits. You can find non abrasive liquid products to remove headlight oxidation on ebay.
Discoloration can be caused from a number of things, oxidation is number 1 and sun yellowing as a result of the removal of the UV layer during a restoration is 2. If the yellowing is a result of a restoration, You can try to sand off the yellowed clear coat . However if the lens itself has yellowed, no amount of sanding will help.
If its discolored due to surface oxidation a non abrasive pure liquid oxidation remover is the safest route to take.
Pittman's Original One Step ALR worked for me, It took a few seconds on each side. Really easy to use, just wipe it on and the results were instant. My lights were really old and worn. Now they look great, I passed inspection and I can see much better at night.
http://www.ibc34.com/Onestep.html

Pam works as will any oil; clean motor oil or vegetable oil. Better still, use paste wax. I keep a can of Johnson's floor wax for the plastic windows in my jeep soft top. Just be sure to start before the very fine (hairline) cracks and discoloration become too advanced. Then you need rubbing compound or the like. Filling the tiny cracks is what the oil or wax does. The cracks distribute the light in a random pattern and cause the cloudy look. Just polish well after application.
just wanted to let u know- cerama bryte glass cook top cleaner made my headlights look brand new and its cheap just takes some elbow grease
I replied with this idea on another person's thread-- I wash cars at Infiniti on weekends, and they have a spray degreaser that works wonders. I used it on my 92 Saturn's windows, wheels and on the headlight covers. They all look awesome now. Maybe you can drive by your dealership if they have a wash bay and ask for them to spray it on and rinse it off for you (no scrubbing or anything required-- it's really strong stuff, keep it off of your paint).
I know this is going to sound crazy but it works. I found this online on a tip page. Take a can of spray like Pam or any kind of cooking spray and spray it onto the light covers. Wipe with a soft cloth. It really works...my husband tried it on his old Crown Vic and it let more light from the headlights come out.
Here are a couple of ideas I am trying for my 1992 Dodge Caravan:
1. Using Soft Soap cleanser on them. This could do it without scratching the plastic.
2. You could replace them from a junk yard. They can WAY LESS expensive compared to buying them new.
Sincerely,
Karen in IN
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