[Rev.Vassago]

Originally Posted by golfhobo

While hooking the dolly to the back of the FRONT trailer, and my codriver holding his foot on the brake while I did so..... I heard/noticed a "constant and PERSISTENT expression of AIR from the BLUE airline BEFORE it got to the "glad hand connection."

The POINT is this, as I'm afraid I'll lose many of you if I don't keep it short:

A SOLO driver could hook up the PRIMARY air line, providing air to the brakes for BOTH trailers, without knowing whether or not it has a MAJOR LEAK in it, because he has no one to apply that pressure to test it. The OLD trucks HAD such a configuration.

The driver would notice a major air leak simply by holding his foot on the brake and seeing the air pressure gauge dropping. If he didn't see it, he wasn't paying attention. I'm sure a minor air leak could go unnoticed, but not a major one.

[bigtruckman]

Originally Posted by Rev.Vassago

The driver would notice a major air leak simply by holding his foot on the brake and seeing the air pressure gauge dropping. If he didn't see it, he wasn't paying attention. I'm sure a minor air leak could go unnoticed, but not a major one.

i agree with the the Rev.

[golfhobo]

Originally Posted by Rev.Vassago

The driver would notice a major air leak simply by holding his foot on the brake and seeing the air pressure gauge dropping. If he didn't see it, he wasn't paying attention. I'm sure a minor air leak could go unnoticed, but not a major one.

Okay, REV... you have a valid point (and Bigmon agrees.) I've never CLAIMED to be an expert on these "doubles." I HATE them! Give me a 53 footer anyday!

But, My point is that MANY of our drivers are solos, not doubles, and when backing up the front trailer to the dolley sitting in front of their back trailer, there is NOT ENOUGH application of the brakes to notice an air leak of this type (because the TRACTOR brakes are doing the job.)

Once "hooked up," the driver may very well leave out of the yard with only a few minimal and short applications of the brakes (again.... the tractor brakes will give the appearance of a complete system.)

The ONLY sure way to notice a leak of the blue line on a set of doubles, is if ONE driver is in the cab, standing on the brakes, while the other driver is outside and AT the "scene of the crime."

Apparently, older trucks allowed a driver to apply the "Trolley bar" and LOCK IT DOWN (often used for parking) that would allow him to make an "operational test" of the primary brake system, when working alone.

When "switching" trailers with another driver (butthead) I have twice in one year found out that the primary brake system was shut off at the front trailer.... giving me no brakes for my back trailer.

Unfortunately, without an APPLICATION of the brakes in the primary system, this mistake cannot be noticed by a solo driver of doubles.

I am ONLY making these points for the education and consideration of newer drivers.... LIKE MYSELF.... who need to constantly consider ALL "possible" failures or mistakes that could cost lives!

There is a reason that a major part of CDL testing is understanding the "Air brake system." Although I had to correct my teacher in CDL school, I STILL have some misunderstandings of it. If "I" do.... I'm sure that I am not alone! :hellno:

Stopping these behemouths is a major part of our job! Fruck the HOS stuff! Make sure you understand the multiple airbrake systems on your rig.... and make sure they are working!

[Windwalker]

Originally Posted by cdswans

The Greeneville Sun - News Story

What wouldn't any guy give for a couple of extra inches?

Think about it... About 10 or 15 years ago, some IDIOT started ordering trailers that were 57 feet long. Wouldn't you like to try to make sure THAT clears the tracks? I don't know what the "great Pumpkin" did with theirs, but I do know that Dart cut theirs down to 53 feet. Most states had the common sense to keep them illegal, so they did not become popular.

[Rev.Vassago]

Originally Posted by golfhobo

But, My point is that MANY of our drivers are solos, not doubles, and when backing up the front trailer to the dolley sitting in front of their back trailer, there is NOT ENOUGH application of the brakes to notice an air leak of this type (because the TRACTOR brakes are doing the job.)

Once "hooked up," the driver may very well leave out of the yard with only a few minimal and short applications of the brakes (again.... the tractor brakes will give the appearance of a complete system.)

Then that driver didn't do a proper PTI.

The ONLY sure way to notice a leak of the blue line on a set of doubles, is if ONE driver is in the cab, standing on the brakes, while the other driver is outside and AT the "scene of the crime."

Apparently, older trucks allowed a driver to apply the "Trolley bar" and LOCK IT DOWN (often used for parking) that would allow him to make an "operational test" of the primary brake system, when working alone.

New trucks do that as well. I know mine does. Volvo is the only manufacturer that I'm aware of that has trolley bars that pop back up when you let go of them. If others have implemented them, it's news to me. But no matter. A simple solution is to hook a bungee cord to it, and then you can get out of your truck at will to inspect the brakes. Apparently that's too much work though.

[golfhobo]

Originally Posted by Rev.Vassago

Then that driver didn't do a proper PTI.

You MAY very well be correct. However.... to PROVE it.... how about showing me an FMCSR that requires a solo driver of a double combination to "rig" his trolley bar to apply constanst pressure to his primary brake line, while he gets out and checks the connections behind the number one and the number two trailer. Maybe there IS one..... but, I haven't SEEN it. :hellno:

For that matter.... how does a driver pulling a 53 footer know for sure? Oh yeah.... the "lab test." Tell me, Rev.... do YOU do that everytime you get into your truck for a daily run?

[ssoutlaw]

Originally Posted by Rev.Vassago

Then that driver didn't do a proper PTI.



New trucks do that as well. I know mine does. Volvo is the only manufacturer that I'm aware of that has trolley bars that pop back up when you let go of them. If others have implemented them, it's news to me. But no matter. A simple solution is to hook a bungee cord to it, and then you can get out of your truck at will to inspect the brakes. Apparently that's too much work though.

My Mack will pop back at you!!

[Rev.Vassago]

Originally Posted by golfhobo

You MAY very well be correct. However.... to PROVE it.... how about showing me an FMCSR that requires a solo driver of a double combination to "rig" his trolley bar to apply constanst pressure to his primary brake line, while he gets out and checks the connections behind the number one and the number two trailer. Maybe there IS one..... but, I haven't SEEN it. :hellno:

The FMCSA regulations do not dictate how a PTI is to be done. They only dictate what items need to be inspected. And all brakes are on the list.

[Orangetxguy]

GH....the only airline a "trolley bar" or "johnnie bar" activate, is the RED one. The redline only activates the trailer brakes, whether it is a 20 foot trailer or a 53 foot trailer, or 2- 28 foot trailers in tandem. (I think I got that right....I'm tired)


The blue line is only activated by the foot treadle.

[Ridge Runner]

Originally Posted by Orangetxguy

GH....the only airline a "trolley bar" or "johnnie bar" activate, is the RED one. The redline only activates the trailer brakes, whether it is a 20 foot trailer or a 53 foot trailer, or 2- 28 foot trailers in tandem. (I think I got that right....I'm tired)


The blue line is only activated by the foot treadle.

And the prize goes to OTG..... the first one to get it right!!!!