I have been using 303 protectant on my tires and toneau cover. Good enough for me.

 

I think DrEvil hit part of it on the head. I use it a lot and it makes whatever dressing go one and the most important thing, it looks clean, not just shiny.

I used STP whatchamacallit in the yellow bottle. It's late and my brain is shutting down for the night! I spray it on a wet, but well rung out open cell sponge and wipe it on. It might take 3-4 coats lapping the truck to finish, but it goes on good and clean. I use as many coats as I need to slowly get that uniform sheen. Doing it this way also makes it easier to coat everything including around letters etc. on the tire.

 

I use the eagle one or armorall stuff