[miahi]

This happened to me in the car when adding a new kind of windshield wiper fluid over the old one. It did not clog the pipes, but made the resulting fluid very slimy, and it could not be wiped out by the wiper blades. The result was that the windshield became translucent and very hard to see through. When it stayed longer on the windshield, it frosted like ice, making it even harder to see through. I had to stop at a service station and drain all that fluid out, then fill the washer fluid tank with water to clean everything.

The new fluid by itself was fine, it was just the combination of the two that created a reaction.

[ollie87]

Didn't happen to be a BMW did it? It was a big issue for a while.

[miahi]

Nope. A quite old VW Polo. Not sure how it could be car specific.

[ollie87]

Different brands use different formulations, apparently the brand that the dealership puts in at BMW/MINI doesn't play nicely with some of the brands from supermarkers.

More of an issue for newer cars though, I will give you that.

[fred_is_fred]

Because clearly BMW sells it's own special washer fluid for $40 a bottle.

[ollie87]

Nah, BMW uses tablets for it's screenwash that are about £7 for six, each makes 5 litres. BMW Part number: 83122298202

Less shipping cost/environmental impact too.

30 litres for around £7 (plus a few pennies for water) doesn't seem bad to me.