Auto body repair & detailing/Detailing
What do you recommend to put on a black plastic bumper to bring the luster back? Something that will last longer than a weekend.
I am sorry this took so long to answer.
In the past most preservatives I have used to rejuvenate the black bumpers have been temporary, as you have found out. Newer items on the market that I have seen on TV, but have not tried, have been around for years in one form or another. They are a coating that when applied make the bumper darker and shiny. An old trick that I used to do was use floor wax. This worked like those types preservatives. Buy a GOOD brand, as the cheaper waxes tend not to give the results you are looking for. I have used industrial or commercial floor was with great results. A bit pricy but worth it.
I would try a small area at first to see what the results are. Try it for about a week before doing the whole bumper.
You might see that the bumper has a pattern in it as it has aged. This is the plastic starting to dry showing the manufacturing marks. Thoroughly clean the bumper. A pressure washer does wonders if you slowly pass over the bumper from about 1'. If you don't have a pressure washer a self-serve car wash in your area might have one. No pressure washer and the hose and water from home will work, itís a bit harder. Using a multi-purpose cleaner and a stiff brush scrub a section at a time, rinsing as you go along. Let dry thoroughly. Apply the floor wax to a towel or sponge applicator. Wipe on smoothly, making sure there are no drips. Allow to dry. Do this in the shade or garage.
You can also use this for other vinyl areas that have faded. One thing, sometimes when the area gets wet after application, you might notice white spots from moisture. These will dry and disappear fairly quickly.
Please let me know how this works.