Newmar Ventana air brakes

Tom/Barb wrote:

wolfe10 wrote:

That is why there are two "cans" on the rear brakes-- one for service brakes, one for emergency/park brakes.

I have 1 can each side of the rear axle, and 1 each side of the front.

all 4 have the hole for the "T" handle release for when there is no air and the vehicle must be towed.


Yes I have the big yellow button parking brake, that will dump the air of the rear Axle.

Tom/Barb,
Bretts (Wolf) explanation of how air brakes in general work, was accurate minus a detail. I don't think he meant there were TWO brake cans on each REAR WHEEL, per say. Without contradicting what Brett stated, I would like to re-describe what I think he meant. There is a SINGLE brake can on each rear wheel. But, unlike the front brake cans, which have a single function, the rears are what's called a DUAL FUNCTION brake can.The rear brake cans have different designs. Some look like two, stacked cans, one on top of the other. While others appear to be a single can. Both are a dual function can.

In that, the can is divided into two sections. One section is devoted to air application for service brakes. The other section is dedicated to a large spring that applies the brakes, when called for. . And, that happens when you PULL the yellow knob on the dash. When you pull on it, that valve releases the air pressure that is used to hold back the springs, in those cans. When the springs take effect, they apply the rear brakes ONLY, TO BE USED AS PARKING BRAKES.


That is a DOT regulation. Parking brakes MUST be applied MECHANICALLY. They cannot be applied by air or, hydraulics.

When you press on the "treadle" valve (brake pedal in the cab), it applies and routes air to ALL the brake chambers. That air, is regulated via that treadle valve. The more you push on it, the more air pressure is sent to the brakes, ALL OF THEM. I hope this helps clear things up a bit.
Scott