I used to use Armor All on my 80's bumpers with the same results. A year ago I tried Black Again from IPD. It is a clear thick liquid, very easy to apply, To my surprise it did make the bumpers and trim strips black again, and they stayed tht way! I have only reapplied it once, and it was not that necessary to do so. Also used it on daughter's '92 240. I still use Armor All inside the car. Keep the dash looking good with the occasional treatment with the Armor All wipes. I have used the Armor all on the window scrapers, they are still "good" after 23 years of wet Oregon weather.