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· Registered
2006 Chrysler 300C SRT8
33 Posts
Discussion Starter · #1 ·
By Tork Monster (Jay)





TIME REQUIRED: ~1 hour (plus time for headlight removal if done)

-Tool set to remove headlights (optional)
-400, 600, 1500, 2000 grit sandpaper
-Auto body "softpad" sanding pad
-Low-speed buffer (optional)
-Fine polish pad for buffer (optional)
-Meguire's Mirror Glaze #17 Plastic Cleaner
-Meguire's Mirror Glaze #10 Plastic Polish
-Masking tape
-Clean polishing cloth
-1-2 bottles of Heineken (optional)

After a number of years on the road (or one trip to California) the polycarbonate headlight lenses and/or foglights on your car may become scratched and pitted. After some time this will leave them dull and hazy to the point you would consider replacing them.
Thankfully, this is easily remedied with block sanding and polish, just like wet-sanding paint.

Here is a pic of my headlights before I polished them. I wasn't planning on doing this, but they looked so bad when I had the car apart I couldn't bear installing them without doing a bit of clean-up. Although this was done on my 300C, the process will work for any polycarbonate headlight or foglight.

1)- It is best to remove the headlights from the car to polish them to avoid scratching the paint on the surrounding bodywork. I have not done this on an R-Class, but it was pretty easy on my 300. However, if this is not possible, wrap the fenders with masking tape to protect them.

2)-If the headlight is removed, cover the openings left from the removed headlight bulbs so no dirt or water gets inside the housing during the procedure. Clean the headlight with soap and water, and dry it completely.

NOTE: Disregard the extra wiring shown in this photo. This is for the halos and LED lights installed in my headlights, not found on standard Chrysler products.

3)- Use a small bowl filled with water to rinse the sanding pad and add water to the area being sanded. The water prevents build-up of the material being in the sandpaper, keeps the sanded area clean, and allows a finer, more even cut surface without scratching.

4)-Start with 600-grit sandpaper, wrapped around a softpad, and dampened with the water. Sand the surface back and forth in one direction only (not circular). If the pits/scratches are bad, you may start with 400-grit paper first, and continue with 600-grit on the next step.

5)-Use a squeege to "clean" the lens and see where the sanding has removed the pits/scratches, or where further sanding is required.

6)- Once all of the original pits/scratches are removed, step up to the next finer grit of sandpaper, 1500-grit. This time, sand in a direction perpendicular to the previous grit. This practice allows you to easily see all of the scratches left from the previous coarse sandpaper. Use the squeege to check in good light for scratches left from the previous grit. Continue sanding until all scratches are removed.

7)- Change to the 2000-grit paper and sand the lens at a different angle once again to be able to clearly see any scratches left by the previous grit.
There is often a release agent (for the plastic mold) on the surface of the plastic that must be removed entirely with the sanding or you will see a cloudy area where it remains. I did not sand enough on my first run at this and you can see this area in the center of this headlight in this pic.

The headlight will look dull at this point:

8)- Clean the headlight and get your polishing buffer. Use a buffer that will spin at low speed; a buffer set at high-speed can melt the plastic. Use a buffing pad made for fine polishing, like the foam pads. The polishing can be done by hand, but it does take l o n g e r .

9)- Meguire's products are the most popular and available. The two that I use are shown below.

10)- The #17 Cleaner is a mild abrasive used to remove scratches. This is the compound to be used with the buffer. The #10 Polish should be applied by hand with a clean soft cloth until the headlight lens looks shiney new.

I was pressed for time on this, as I was not planning on doing this initially and really needed to get the nose back on my car before nightfall. I didn't sand as far as I should have to remove all of the original pits, and cut some corners to get it done fast. The end result is much better than what it was in the start, but I plan on doing this again thoroughly when I get the chance.

In this "after" picture, you can see the improvement, although there are still many nicks that I am going to have to attack later

This is too easy to do... It's a great, inexpensive way to make your car look like new!

NOTE: I posted this in the R-Class section, where AsianBlackR350 posted a request for DIY threads. Admin may move this and/or edit as appropriate.

· Registered
08 R350, 07 Acura RL, 1989 Honda Shadow VLX600 (10K miles)
786 Posts
Look good.
You should apply Meguiar's HEADLIGHT Protection (UV protection).
It will help headlights clear and last longer (without this coating, it will turn yellow sooner).

· Registered
'07 R320
148 Posts
I did the same thing to my old e320 wagon. I used one of those 20 dollar 3M kits from amazon. Pretty much the same thing...same result!

I always wonder if it would be good to install those clear plastic/vinyl headlight protection films after this procedure.

Will they prevent yellowing / pitting?
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