:iagree:100%If you're talking about the black plastic and not rubber, for example the step plate on the bumper or rear glass handle, most of the 'treatments' only cover them up temporarily. (I've tried several and unless you really work them in, the effect washes right off). What seems to have some lasting effect is to get a good nylon/polyester covered sponge or fairly stiff bristled brush and scrub the heck out of them.....the lightening on those textured plastic parts is more deposits than fading. Once or twice a year I simply scrub the heck out of them using a good auto wash & water mix, which removes all the film making them appear faded. - I was shocked to say the least that its deposits and not fading. It takes some elbow grease, but those black plastic parts will again appear black or at least charcoal in color. You can then follow up with a light coat of your favorite detailing plastic protectant.
Been doing mine like that since we've owned our 07TB for 2 1/2 years now. Scrub the heck out it with a nail brush(the ones for your fingers), and then followed up with Back to Black.
One of the tricks I do, is to scrub the Back to Black into the parts, using ample amounts of the B&B. Allow it time to soak in(I wait 15-20 mins), then buff it off, constantly using a clean part of the cloth(s).