Greasy window

At a gas station my wife washed her rear window. I think someone sabotaged the windshield washer fluid. After she squeegeed the fluid off, it left a thick film of greasy stuff on the window. She couldn’t see through the window and tried for a long time cleaning it with wet wipes. When she got home, we used Dawn dish soap which helped but still left a slight film. Today I took a rag and sprayed a little WD 40 on it and wiped it down. That helped a little more. My question is what can I use safely to remove this. I’m tempted to use Wd40 more liberally. And has anyone heard of this happening that could identify what it is.

Brake parts cleaner.

Tester

I’d skip the wd40. Straight isopropyl alcohol and use a newspaper, followed up with glass cleaner.

I was afraid that might damage the glass. Is it safe? Have you tried it?

I use it to remove decals/stickers from automotive glass.

Tester

I also vote for isopropyl alcohol.

If someone put coolant (especially concentrated coolant) in the bucket, I’d expect something like what you described.

Yeah. When I read the title “Greasy window” I immediately thought of antifreeze vapors on the interior side of a windshield: leaking heater core.

Heater core?

Tester

That is a good thought. It is feasible that an unknowing employee put antifreese in it, but this seemed too thick for that. I’ll try the alchohol first. If that doesn’t work I’ll go to the trusty brake parts cleaner. I know that will work, I just wasn’t sure if it was safe to use until now.

Denatured alcohol (50/50) is even better than isopropyl. But most people probably have isopropyl on hand rather than denatured. I’m just a painter at least some of the time, so I always have some denatured. It won’t hurt the glass. One of the best glass cleaners there is.