Changed my car last week and the windows and windscreen are covered in dry water marks. Looks like when cleaned the car has not been dried properly, hence the marks. It’s a bit of an issue on the windscreen when the sun shines through. I’ve tried normal glass cleaners with no luck and also distilled white vinegar, again no joy. What’s next? Anyone have any experience or ideas?

Have you cleaned both inside and out?
Is there something in the reservoir polluting the windscreen wash?

Sounds like you need a cutting paste. They make ones for windshields. Or, original tcut as it has zero wax/polish.

I get this when I wash the car using a shampoo with wax in it, great on the bodywork but leaves watermarks on the windows. I would have thought the vinegar would remove it but maybe a more specialist wax remover might help?.

A friend has just recommended t cut, will try that.

I had this on a 2nd hand car I bought. Had to use G3 and an electric polisher. I couldn’t believe how sturdy the bloody things were. Took hours.

Good luck is all I can say, I hope it’s an MX5 and not a big 4×4 like mine.

Try this dodo juice
https://www.amazon.co.uk/Dodo-Juice-Clearly-Menthol-Cleaner-x/dp/B004GU51I6

It’s the polymers in the car shampoo. The ones they use in car washes are terrible for this. Try ordinary car polish, which is mildly abrasive. I would think T Cut might scratch the glass.

I use toothpaste and washing up liquid on my screen when its greasy
works a treat

Use a Foam non abrasive scouring pad ( not metal for obvious reasons) or a bug removal pad ( foam sponge with a mesh net ) on the Windows next time you wash the car. You can use a car specific glass polish too but don’t use car polish or t cut unless you like a frosted glass effect…

Autoglym glass polish will do the trick, along with some grease from your elbow.

https://www.autoglym.com/car-glass-polish

+1 for Auto Glym car glass polish.

I wouldn’t risk it with my car bodywork polish or T-cut, which are designed for paint. Could ruin the glass.

Looked into this a while ago & apparently 00 grade steel wool is what you need , thats double zero grade. Never tried it because I cant buy it here , but when I get some I will use it.

We used tcut to polish out 220grit sanding marks out of acrylic in design tech product prototyping projects, so it isn’t going to damage glass.
But yes, glass polish is available

When I used to valet cars as a teenager we had a glass polish that was like old style Windolene – it came as a cream with a fierce solvent that evaporated fast leaving a chalky deposit, which you wiped off with a cloth. It was amazingly effective but I suspect it may have disappeared now due to H&S regs. Is present-day glass polish as effective?

We could get a filthy trade-in back to showroom condition in an hour with the stuff we had there.

I know you said you tried vinegar but you need to dip a bit of kitchen roll in white vinegar and keep that sitting on the mark for some hours to shift it.

you only need more aggressive products if it’s gone beyond a water mark and actually ‘etched’ into the glass.

Source: kept african cichlids which are kept in extremely hard water, any drip marks the aquarium

Try wurth active foaming window cleaner. Wurth stuff is amazing particularly the screen wash which comes in little one shot bottles so you can always have some in the car. The mechanics hand cleaner p’s all over swarfega too