airbags

If the forklift driver is racing in and out of your trailer and bouncing around -- this is normal. It is worse if you don't slide your tandems to the rear.

You've obviousoy got an air leak somewhere. Get a spray bottle, fill it with soapy water, and spray every valve & fitting until you find it. But an inaudible leak is perfectly legal as long as you're not losing more than 2psi/min for your tractor (tank totally empty in 2 hours). Sounds like you're legal...

Tank 1 should come up, tank 2 should go down. They will equalize -- normal...

What do you mean brake pressure? Like when you're cruising down the road the tanks are reading 90psi all the time? Or during braking the air pressure drops to 90 and then rises again?

It honestly sounds to me like you need to study the air brake section of the cdl manual.

 

CT state air leak test for a T/T, motor off, buttons in foot on floor (no service brake) is no more than 3psi in 1 min.
Service brake on (foot on pedal) should be no more than 4psi in 1 min.
Motor on 85psi to 100psi @ 1200 RPM in 45 sec.
More air loss or longer build time you have to get system serviced.
Don't know how an air bag system would play into all this. Guess I will ask in school on Monday.
Dave ----

 

Sounds to me like you have a slight air leak and you're making it out to be a huge safety issue when it isn't at all.

 

Sounds like you may have more then 1 air leak issue going on (on different sides of the system). If all buttons are pulled and 1 tank is virtually empty next morning, that's one leak that you'll have to find as was discussed in an earlier post.

Have you switched trailers since you started with this thread? Same Issue? If so, you may have a busted brake diaphragm on the tractor. Get some place quiet, shut off the engine, leave brake buttons pressed in, roll down your window and mash the brake foot pedal about like you were coming to a stop while heavy on a steep hill and hold this. If you hear air hissing or "flowing" outside (or behind the dash), you have a air leak (when using brakes) that could get you in trouble.

Under normal operation,coming to a complete stop should not deplete your air supply more then about 5-10 PSI. Another thing FYI, brakes that are far out of adjustment require a lot of additional air volume to do the braking job. Also, how long does it take to reagin that 30 PSI lost?

There are all kinds of leaks that happen at different times and you need to learn how to troubleshoot all of them.