My hypothesis differs somewhat from what I've read here. It is, by no means, scientific!

The "scratches" in my window appear about a quarter of the way up from the bottom of the window. When I open my top, I notice that the window fold just happens to hit that area.

So, I believe that a light dust is lodged between the folded area. The folded areas rub as a course of being driven. Friction equals scratches.

Although I clean the window (outside) before dropping the top, the scratches still appear. In the past, I hadn't used the tonneau when driving the car. I'm thinking it would be a good idea, as it would likely keep the dust out of that area. Another precaution might be to place a strip of felt where the window would normally fold on itself. (Perhaps the "tube" I read about would help too...I don't know.

 

use plexus or the stuff 3m makes, cheap and makes a huge difference, I think the scraches are probably from dirt and dust in the top "well" where it fits and the plastic rubs there....just my .02

 

Welcome to the wonderful world of owning a convertible!

 

saw an sl 600 mercedes this past week - plastic rear window for a $100K + car.

 

Someone in the forum suggested to get rid of the crease in the rear plastic window, to use 2 quart of hot water (170F) and pour it side-to-side on top of the crease. Then park the car outside with the sun and as it dries the crease should disappear.

Has anyone try this? Would the hot water damage the plastic in any way?

 

I haven't tried it, but that was actually a reccomendation in one of the TSB's. There's a TSB on the plastic windows and how to treat and take care of them. You can always just leave it in the hot sun for a few hours.