Screenwash ratios

Merlin5 · 19 Nov 2019 at 16:09

Just bought a 5 litre bottle of concentrate from Halfords. Says 20% concentrate to 80% water is effective down to -1.5c, and 50% concentrate with 50% water down to -4c. What ratio are you guys using? I don't know how cold the weather is likely to get, but I'm thinking of trying maybe 35% concentrate to 65% water, probably be good to about -3c?

brendy · 19 Nov 2019 at 16:19

Never really scientific, a few glugs of screenwash then fill it up with water. Job jobbed

If I feel the weather is going to be very cold, Ill add another glug for luck.

Lakeland · 19 Nov 2019 at 16:31

Personally I hate that stuff. The best I’ve used is either VW or BMW brand screen wash. With a 50/50 mix it’s like spraying your window with de-icer, though when we get ice none stop I put it in at 80% de-icer and 20% water.

If you’re not sure just mix some up and leave it out over night or pour on the window in the morning and see if it helps clear up the ice.

Lakeland · 19 Nov 2019 at 16:33

Lakeland said:
Personally I hate that stuff. The best I’ve used is either VW or BMW brand screen wash. With a 50/50 mix it’s like spraying your window with de-icer, though when we get ice none stop I put it in at 80% de-icer and 20% water.

If you’re not sure just mix some up and leave it out over night or pour on the window in the morning and see if it helps clear up the ice.

I should add, if you have a bmw you should stick with their product as others can and do block up the filters and it isn’t cheap to fix it.

Drumroll · 19 Nov 2019 at 16:59

Lakeland said:
I should add, if you have a bmw you should stick with their product as others can and do block up the filters and it isn’t cheap to fix it.

This. Sound advice.
Saving few pounds not worth here.

Finglonga · 19 Nov 2019 at 17:02

I use the pre mix (Berry Flavour) as it goes down to -10C, Got 4 gallons of it last week for our cars. Used it for years on BMW's and VW's with no issues.

Psycho Sonny · 19 Nov 2019 at 17:08

Merlin5 said:
Just bought a 5 litre bottle of concentrate from Halfords. Says 20% concentrate to 80% water is effective down to -1.5c, and 50% concentrate with 50% water down to -4c. What ratio are you guys using? I don't know how cold the weather is likely to get, but I'm thinking of trying maybe 35% concentrate to 65% water, probably be good to about -3c?

How much was the screenwash. If cheap just do 50/50. If Expensive then do 20/80 as 1.5C isn't a huge difference. However it was -8C here last night in Scotland.

HoneyBadger · 19 Nov 2019 at 17:12

I use ready mixed stuff

Conscript · 19 Nov 2019 at 17:19

Are Halfords still being a bit sneaky with concentrate/premix?

If I remember, last year, they sold the Berry scented concentrate, rated to -10, in 5 litres bottles for about £5. But it's only rated to -10 if you use it neat.
Whereas they sell the premixed stuff, also rated to -10, in 5 litre bottles for £4.50.

Which suggests to me that its exactly the same product, but they charge 50p more for the concentrate. Are they hoping that most people just automatically assume that concentrate is better value because it can be diluted?

inogen · 19 Nov 2019 at 17:39

Lakeland said:
I should add, if you have a bmw you should stick with their product as others can and do block up the filters and it isn’t cheap to fix it.

MrPotato said:
This. Sound advice.
Saving few pounds not worth here.

I've been running an e46 for nearly 5 years and have never put BMW screen wash in. I have used PIA as I have silicone wipers and that works well with them, but generally I just use cheapo concentrate and/or plain water in the summer.

I do like good clean windows though and go through loads of it.

Merlin5 · 19 Nov 2019 at 18:27

Psycho Sonny said:
How much was the screenwash. If cheap just do 50/50. If Expensive then do 20/80 as 1.5C isn't a huge difference. However it was -8C here last night in Scotland.

Yeah, only a fiver for a 5L bottle. I'll probably do 50/50 then.

Conscript said:
Are Halfords still being a bit sneaky with concentrate/premix?

If I remember, last year, they sold the Berry scented concentrate, rated to -10, in 5 litres bottles for about £5. But it's only rated to -10 if you use it neat.
Whereas they sell the premixed stuff, also rated to -10, in 5 litre bottles for £4.50.

Which suggests to me that its exactly the same product, but they charge 50p more for the concentrate. Are they hoping that most people just automatically assume that concentrate is better value because it can be diluted?

Good point. Does that mean the ready to use stuff could also be diluted?

inogen · 19 Nov 2019 at 18:47

Merlin5 said:
Good point. Does that mean the ready to use stuff could also be diluted?

You can dilute whatever you like.

I've gone whole winters just using water before.

Conscript · 19 Nov 2019 at 18:55

Merlin5 said:
Yeah, only a fiver for a 5L bottle. I'll probably do 50/50 then.

Good point. Does that mean the ready to use stuff could also be diluted?

I reckon so. I'd just buy the premixed and dilute it as I would the concentrate.

Merlin5 · 19 Nov 2019 at 19:04

Conscript said:
I reckon so. I'd just buy the premixed and dilute it as I would the concentrate.

Hmm, well, 50p is 50p and yes, that really is a bit of a con from Halfords. I haven't opened the bottle so I might go back and change it to premixed.

Conscript · 19 Nov 2019 at 20:57

Also, the premixed stuff is 2 bottles for £7.50 on their website at the moment.

Vanquish-Storm · 19 Nov 2019 at 22:24

Does a windscreen not go lower in temp that the ambient temperature?

mccarf · 19 Nov 2019 at 22:42

Bought some last year and just chucked it straight in. It was the most foul smelling screen wash I've ever experienced, I mean when I sprayed it onto my windscreen the smell would actually punch me in the face. Looked at the back of the bottle and it was good for something like -60 degrees. Ah okay that's why!

Lakeland · 19 Nov 2019 at 22:54

inogen said:
I've been running an e46 for nearly 5 years and have never put BMW screen wash in. I have used PIA as I have silicone wipers and that works well with them, but generally I just use cheapo concentrate and/or plain water in the summer.

I do like good clean windows though and go through loads of it.

To be fair I think it’s more of a problem with newer cars. I don’t think it’s a problem with the bmw system but more of an issue with mixing bmw style screenwash with other types. If you run it dry or run water for ages I suspect you can swap to something else without a problem (that’s me guessing!) but tbh the bmw stuff you get in a 5L container is so good I just run it all year with varying ratios of water.

ShiWarrior · 20 Nov 2019 at 13:12

i always use cheap supermarket Screen Wash for years, never had any problems
about £1.50 for 5 Liters (Concentrate)

use more in winter to prevent the screen wash pipes from freezing and cracking

robj20 · 20 Nov 2019 at 13:42

I've always used this. Goes to -45c of you use it best.

https://www.elitecarcare.co.uk/product/autoglym-super-strength-screenwash-concentrate-5-litres/

20% will do -6c which is what I use over winter.
So it makes 25 liters.