Brake fluid on a windshield?

This was strange enough that I thought I’d ask here. I was at a strip mall that has a small, somewhat shifty-looking repair shop in it. While I was waiting for something else, I saw one of the mechanics come out to a car in the customer section of their lot with a big bottle of brake fluid. He poured it on a rag and rubbed it onto all 4 corners of the windshield. Just the corners, probably about an 8 inch circle in each corner.

I can’t fathom what he was hoping to achieve, but figured a pro on here might have insight. Any ideas?

If it’s not DOT 5, I guess it could serve as a solvent for high-powered cleaning. I certainly hope they kept it away from all paint and rubber, though.

How old was the car? Did the shop install glass?

In the GOOD OLE DAYS auto glass was pried into and out of a rubber groove. I recall body shops lifting up the rubber at the corners and wiping brake fluid between the rubber and glass to speed getting the glass free and then installing the new glass.


Older. Mid-90’s Kia. But he rubbed it on top of the glass, which struck me as bizarre.

I don’t think he took much care to keep it away from the paint either. :confused:

This is not a shop I would take my vehicles to.

Removing overspray? Tow sticker adhesive?