Truck Shop ... As another Heavy truck ignorant...
Is this the cause of the poor condition of the rotors ?
"...Air disc brakes cause drivers to over use them because those react quicker..."
I've noticed many drivers applying their brakes constantly because they follow too closely. While I with enough distance, just let off the gas and free wheel.
When the automated manual transmissions became the choice. Along with it came a learning curve, coupled
with air disc the curve grew.
And this info is for anyone on here who uses trucks in their business or is looking to buy a truck with
AMT & Air Disc. Air Disc can be used but mainly on the steer axle not the drive axles, It works well on
steers because of reduced air pressure. The AMT gear boxes in auto mode must be operated with jakes
on all the time weather operated by foot throttle or in cruise control mode.
When on a highway with slight rollers/hills the AMT will go into coast mode, if the jake is not on to
constantly take control of braking to keep correct road speed the driver will find himself constantly
riding the brake. When descending a grade {especially} a long grade the proper way to keep control
of vehicle without riding the brake using the jakes is to,--{push the mode button to manual mode with
jakes on till rpm is low enough to manually down shift again without over revving/going past 2,200 rpm.
Same as any manual transmission. With 3.70 ratio rear drives at 105,000 lbs GVW you can descend a
10 mile long steady 6% grade at 38 to 40 mph with a Cummins X15 or a Detroit DD15-16 {And never
touch the brake} manually locked in 7th gear mode.
Part of the problem is air disc when cool tend to give the driver a feeling of super braking control.
It causes a driver to run with no safety zone in front of him because he figures his disc brakes are
going to give him better control running up close on traffic, a total false sense of security is developed.
I have had drivers tell me that very thing, they found themselves running harder in heavy traffic.
Now couple that with not having the jake constantly on, in auto mode constantly going into a coasting
situation===one foot on the throttle and one foot on the brake. The other problem no one seems to address
in the industry-The rear rotors are tucked inside the inside drive wheel, with all the fairings these trucks have
deflecting air to reduce drag the rotors get about zero air to cool them, Drums are open around the shoes so
those get some air inside as well as outside. Trucks can automatically lower themselves once at road
speed another 2 1/2" to reduce drag.
The real problem with all of this is it makes people lazy. It's the cost of these brakes/major components
that drive inflation because that's passed on to the consumer just like a lot of other innovations.
A lot of companies bought air disc/ amt----I have yet to find one that will admit it was a mistake.
As far as highway data on truck involved accidents in the U.S. {Not Canada}. Accidents have risen by
quite a bit since air disc arrived, although you won't find one agency source that will point to the latest
innovations as part of the culprit.
A recipe for disaster.