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2017 Forester
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11 Posts
Discussion Starter · #1 ·
HI All,
My 2017 Forester has 27K miles on it and 35 months old.

I think I need to test the break fluid on it before I shell out $100+ to change it.. Who knows.. maybe I will not have to change it after all?

I saw this pen online.


Would this pen be appropriate for 2017 Forester?

Amazon says it is "brake fluid tester dot 3 dot 4" But I have no idea if that is what foresters have.. Does anybody know?

Any other words of advice in relation to this are much appreciated!

Thank you all
 

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17,688 Posts
I guess it may give you a clue for the reservoir but it's not going to tell you what's going on at the brake calipers. Your service schedule will tell you how often it should be changed (I can't recall atm)
 

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2007 Forester Sports XT 4EAT
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2005 Forester Automatic
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495 Posts
The fluid in the reservoir has more exposure to environmental air than the fluid in the calipers and lines. Moisture in the ambient air gets absorbed by the brake fluid, but at some point the fluid gets saturated and starts to allow corrosion or worse water in the low spots. The testers are actually pretty useful, and if the tester shows that your fluid is good in the reservoir, you are ok for a while.

Manufacturers made these new brake fluid flush recommendations in response to some spectacular fails of ABS systems. Did not hurt that it is good money for dealers. But, unless you live in a super humid hell hole of a place, your brake fluid will last far longer.

FYI, why do we use brake fluid that absorbs water? Well, water is heavier than most oils (at least ones that are nice and fluid). That means, if used normal hydraulic oil in a brake system and water got in there, it would gravitate to the lowest points. Like the calipers. And there, it could freeze, rendering your brakes inoperable. So rather than have the water separate, the fluid is designed (esthers, IIRC) to absorb it. But the system is also supposed to be closed (witness the rubber bladder in many older brake cylinders) or close to closed to prevent environmental moisture absorption..

Indianaopolis is not that wet. I'd save my $$
 

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2017 Forester 2.5i CVT
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202 Posts
My 2017 2.5i came with DOT 3 and manual says use DOT 3 or 4. I am nearing 50k and thus have now ordered one of these before my dealer tries to upsell me a brake fluid change!
 

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2019 Crosstrek 2018 Forester XT
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14,921 Posts
I guess it may give you a clue for the reservoir but it's not going to tell you what's going on at the brake calipers. Your service schedule will tell you how often it should be changed (I can't recall atm)
This
 
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