Thankfully manufacturers are starting to spec glass rear windows in many newer convertibles — or crazy-cool retractable hard tops — but if you’ve got one of the “vintage” models, you’re probably graced with clear plastic. After a while they get scuffed no matter how carefully you protect them, and then you’re faced with the big question: Do I try to clean it? And with what?
Back when I worked at an airport, I saw people deal with this on an uber-basis. What do you do when you have the same problem, but with a $30,000 Learjet window? We often used two of Meguiar’s products: Mirror Glaze Clear Plastic Cleaner and Polish. Good enough for Learjet = good enough for Miata, in my book.
The cleaner is a slight bit more abrasive and works well to remove small scuffs and even some scratches. I just apply it to a non-abrasive cloth — olf-fashioned baby diapers work great — and rub. Once the big stuff’s gone, switch to the polish, which is much finer and puts the original shine (and “clearness”) back in the window. Be sure to get it all off.
Of course, you can save yourself some work by making sure you store the window properly. Use the boot (the cover for the soft top for you Canadians) whenever you put the top down, and if you install a hard top for the winter, look for a “hard top boot” that fits under the top and cradles the window in padded softness.
And remember: Seeing out the back is a good thing. Either clean that window up — or replace it.
The cleaner and polish sell for $8 each on Meguiar’s site, and you can find them on the street for around $6 with some searching.