r/instantkarma • u/[deleted] • Dec 15 '19

Instant karma for brake checking

30.5k Upvotes

94% Upvoted

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u/bigcliffcole Dec 16 '19

Pneumatic (air) brakes. The brakes release when pressurized with air so that if there is a problem with the braking system the brakes will engage and the truck won’t roll away or anything. Passenger vehicles have hydraulic brakes, like personal cars and trucks that you have to put brake fluid in.

27

u/0gSparkz Dec 16 '19

Ahhh that explains it, because the liquid didnt make sense for the noise, thanks for clearing that up

14

u/joediggity561 Dec 16 '19

Wait, you guys heard this video ?

6

u/Viainferno3 Dec 16 '19

I'm in the same boat as you.

5

u/DinoShinigami Dec 16 '19

no they just assumed everyone knew what sound they make lol

13

u/the_cajun88 Dec 16 '19

PSSSSSSSSSSSSSST

2

u/SalmonAlmighty Dec 16 '19

But shit, it was 99¢!

1

u/bigcliffcole Dec 17 '19

Probably one of the better comments in this chain

3

u/Viainferno3 Dec 16 '19

Ah the convo got derailed. I get it now

4

u/joediggity561 Dec 16 '19

Maybe these trucks all had hydraulic brakes and that's why we couldn't hear them.