I saw a road sign that said "Brake Retardants Not Allowed until outside City Limits." ?

Question

What the heck are brake retardants?

Answer 1

I like it when you call it, "brake retardants" but the sign should read

brake retarders & the answers that have been mentioned so far are

correct. I'm a trucker of 16 1/2 yrs. now. And the signs usually do read

brake retarders, engine retarders, or engine brakes!

Answer 2

That's very odd wording, but I've seen similar signs for 18 wheelers asking them not to use their "Jake Brake" between certain hours or outside city limits. Those are those noise engine braking devices you hear trucks use once in a while. I have a feeling this is the same message. only written by a bureaucrat.  

Answer 3

They are setups on diesel engines of large trucks that allow the very high compression of the engine to be used as a braking device, particularly on long hills or mountain downgrades.  They are generally very noisy, and their use is often prohibited in populated areas.

Answer 4

Jake Brake!!

Answer 5

Big trucks use the engine to slow down and to save their regular wheel brakes.  This is sometimes pretty noise at night.  

Answer 6

Roads and highways are designed for trucks. This is a conclusion that I have come to after years of highway miles through cities big and small. Cars are secondary in the big transportation scheme.

A brake retardant is when the engine's compression is used to assist the slowing down of the vehicle. Also known as a Jacob's brake. Jake.

They can be loud if switched on but they assist the brakes and reduce the risk of them overheating and failing when carrying heavy loads.  

Answer 7

Do not use your Jake Brakes. Around here all the cowboys that have never driven over the road use them around  town.