How to Restore Faded Black Plastic Trim on a Car (Best Method)

Nothing ages a car quite lack grey, faded plastic trim, and if you care about your vehicle’s appearance then it’s no surprise that you’re looking for a way to restore it. Fortunately, the process is actually really straightforward and you can easily restore the plastic trim back to a dark black appearance by following this guide.

How to Restore Faded Plastic Trim

The best way to restore faded plastic trim on a car is to use a coating such as Gtechniq C4 which bonds to the trim to restoring the black finish and protect it from future UV damage and fading.

Using a trim coating requires very little skill and only takes around 20-30 minutes per vehicle.

Important: Do Not Use Heat

There are a few other “DIY” methods that some people use to restore trim but I would advise against them. One of the more popular approaches is to use heat, in the form of a hair dryer or heat station. However, I strongly advise that you do not use this method.

Using heat to restore the appearance of plastic trim works by bringing the oils in the material to the surface. However, this causes the plastic to become super brittle and damages it permanently. The darkened finish is also very temporary.

In the rest of this article I’ll take you through my preferred method of restoring faded plastic by using a coating.

How to Use a Trim Restorer Coating

Applying a trim coating is actually really easy and quick. Many trim coatings have a durability claim of 1-2 years so you will likely need to repeat the process after that time and keep in mind that there isn’t really a truly permanent fix to restoring trim except to replace it entirely!

Best Trim Coating

There are plenty of trim coatings on the market from various brands like Gyeon, Carbon Collective, Solution Finish, and 303. I have personally used Gtechniq C4 and had really good results with it, so I’ll be using this as an example. I have used it on several vehicles and it lasts 12-18 months before it needs reapplying from my experience.

I’d always recommend using a trim coating, rather than a trim dressing when it comes to restoring faded plastics. Trim coatings are superior because:

  • They last years (not weeks)
  • They do not run or streak in the rain
  • They protect against UV damage which causes further fading

You should be able to identify trim coatings quite easily as they often come in small glass bottles (usually about 30-50 mL) and have durability claims of 1-2 years. Trim dressings on the other hand are typically in much larger quantities (500 mL+) and do not have long durability claims. An example of a trim dressing is CarPro Perl.

Preparing the Trim for the Coating

It is absolutely essential that you prepare the plastic trim properly before applying a restorative coating, otherwise it will not bond properly and will not last nearly as long as it could otherwise. It can also lead to a messy or streaky finish.

Preparing the trim is a simple process though and should only take about 10-15 minutes per vehicle. Here’s how to do it:

  • Clean the trim thoroughly using an all-purpose-cleaner (e.g. Koch Chemie Greenstar) and medium-stiff brush (e.g. Valet Pro Sash Brush)
  • Rinse the plastic to remove all chemical and dirt residue
  • Dry the trim using a microfiber towel. Make sure you get into all the panel gaps and crevices to avoid drips of water interfering with the application process.
  • Use a panel wipe solution (e.g. Gtechniq Panel Wipe), or an IPA solution (50% dilution) on a microfiber towel to remove oils and residues from the plastic.
  • Wait around 15 minutes before proceeding with the coating application to ensure the panel wipe solution has fully evaporated.

Applying the Trim Coating

The exact instructions for each individual trim coating will vary, so make sure you always follow the manufacturer’s instructions. Here’s the process for Gtechniq C4. Note: you should also wear the recommended PPE as described by the manufacturer.

  • Apply about 5 drops to the applicator. You can use either the lint-free cotton pads which come provided, or a suede applicator cloth.
  • Spread the coating onto the trim and ensure even coverage. Work in small sections at a time for best results.
  • Immediately use a clean low-pile microfiber towel (e.g. The Rag Company Edgeless Pearl) to very gently wipe the surface and remove high-spots. It is essential that you do this even if it doesn’t look like you need to, otherwise the coating may flake over time.
  • If you need to darken the trim more, you can apply a second coat after 1-2 hours of applying the first coat.

If you would like to see the preparation and application process in action, check out this video on the Auto Care HQ YouTube channel showing the full method.


Here are some frequently asked questions about the application process.

Are there any environmental conditions I need to consider?

With this being a proper coating, there are some things you need to keep in mind.

  • Work in a well ventilated area
  • Apply the coating in a temperature above 5 degrees Celcius
  • Do not apply the coating in direct sunlight
  • Make sure the coating does not get wet within 12 hours of application

You can apply a trim coating outdoors, but just be conscious of the temperature and make sure the risk of rain is as low as possible.

How much trim coating do I need?

For most vehicles with an average amount of plastic trim, you will only need around 10-15 mL of coating to cover it. However, if you have a car with lots of black trim (e.g. a Mini or SUV), then you will need about 20-30 mL of coating to be on the safe side.

How long does the coating last after opening the bottle?

Gtechniq C4 should be used within 3 months of opening.

What happens if I get the trim coating on the paintwork?

In this event, just wipe the coating off immediately using a clean microfiber towel. It should come off nice and easily. If you are worried about getting it on the paintwork and not noticing, you can also use low-tack masking tape to mask off the areas.

How do I maintain the trim coating?

Simply wash the car as you normally would, using a dedicated car shampoo. Avoid the use of harsh chemicals and solvents (e.g. tar remover) as this can degrade the coating.



Heather is a professional car detailer & valeter based in Cheshire and the owner of Auto Care HQ. A familiar face in the car detailing community, she has written over 200 car detailing guides on and has produced over 165 videos on the Auto Care HQ YouTube channel.

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