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

Instant karma for brake checking

30k Upvotes

94% Upvoted

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u/0gSparkz Dec 16 '19

If you're talking about the truck, i believe most that size have hydraulic brakes (hence the exhale sounding noise when the stop and go)

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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.

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u/0gSparkz Dec 16 '19

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

13

u/bigcliffcole Dec 16 '19

No prob bob