Diesel Pusher Air Brake System

[johnschiesser]

I recently had a low air light warning in the air brake system. I was 500 miles from home. I jury rigged the system to get it home. The first thing I looked at was the air drier. The desiccant filter had come apart and the white powder went all through the air system.

Repair necessitated new air tanks,new foot brake valve,overhaul of the rear brake relay valve and overhaul of the park brake relay valve.. I was able to clean the 5 air lines that go from front to back.The cost in parts alone was about $1000 and about 3 weeks of my labor. I believe that this failure was a result of my neglect on servicing the air drier at least every 2 years or 20000 miles as Freightliner recommends.

Mine went 3+ years and 40000 miles.Just a word of warning to perform regular service on this component. It is easily forgotten.

[ticat900]

My last one went 8 years and 44K miles and still looked like new.

They should last for years and 100+K miles.

[dickandlois]

Hi John,

That is a lot of damage to the air system.

I have gone over 4 years on a filter on my coach, but drove fewer miles. When I had it replaced at the shop the mechanic mentioned that it was in good condition and would have lasted longer.

There has not been a response to date from any other forum members, that mention a similar problem.

Could you expand on your general area of the country that you live and what areas you traveled in and through over the time the failed filer was in the system. The best you can.

The troubling issue for me is the the powder inside the filter was able to migrate through the entire system. I would think the powder would have to be dry. Had it absorbed some moisture, this would have limited its ability to migrate through the system to the extent it did.

I have to wounder if the cartridge was defective or damaged in some way when it was installed. In that case we all could have a failure of this type.

Rich.

[desertdeals69]

When I let my air filter go to long it started pumping oil out the spitter valve. I thought my compressor had failed but talking to a truck shop they told me to change the filter and that should solve the problem. I did that and no more oil coming out of the spitter valve.

[johnschiesser]

Hi John,

That is a lot of damage to the air system.

I have gone over 4 years on a filter on my coach, but drove fewer miles. When I had it replaced at the shop the mechanic mentioned that it was in good condition and would have lasted longer.

There has not been a response to date from any other forum members, that mention a similar problem.

Could you expand on your general area of the country that you live and what areas you traveled in and through over the time the failed filer was in the system. The best you can.

The troubling issue for me is the the powder inside the filter was able to migrate through the entire system. I would think the powder would have to be dry. Had it absorbed some moisture, this would have limited its ability to migrate through the system to the extent it did.

I have to wounder if the cartridge was defective or damaged in some way when it was installed. In that case we all could have a failure of this type.

Rich.

We live in the Sacramento CA area and our travels have taken us to the east coast twice and numerous places on the west coast durring the time since the filter was changed. Most of the travel has been in the west where the air is dryer. I don't know when it started to disintegrate but the desicant was dry and powdery. It lined the tanks with about an eight of an inch of white powder and also went all through the air system including all the air valves. The failure was such that it caused the dryer exhaust to leak excessively not allowing the compressor to build air in the tanks. I made it home by bypassing the dryer with a piece of hose.

My purpose with this thread was to alert diesel MH owners about this failure and the importance of routine maintenance on the dryer.

I believe my problem was due to neglect on my part for not performing the required maintenance on it. Freightliner recommends 2years or 20000 miles. after this fiasco you can bet that I will follow their recommendations.

Thanks for the interest.

[johnschiesser]

My last one went 8 years and 44K miles and still looked like new.

They should last for years and 100+K miles.

You lucked out.

[johnschiesser]

When I let my air filter go to long it started pumping oil out the spitter valve. I thought my compressor had failed but talking to a truck shop they told me to change the filter and that should solve the problem. I did that and no more oil coming out of the spitter valve.

My problem was similar to yours in that the spitter valve was leaking excessively.