98 Discovery air noise

[firecoop30]

I have a 1998 Fleetwood Discovery 36T with a 275 Cummin's. Runs great, but after I turn the engine off, something under the coach releases major amounts of air for about 2-3 minutes after the engine is off. The air gauge shows the air pressure stays at 100, but its still releasing air.

Anyone have any ideas?

[Gary RVRoamer]

This happens without dumping the air from the suspension? It just spontaneously releases air? If so, I would guess you have a major air leak in the brake system or possibly the air suspension. The compressor keeps up with it while driving so the brakes & air bags work, but it bleeds off when you shut down.

100 psi sounds a bit low - my American Tradition runs at 125 psi.

[Always-RVing]

I have a switch near the driver for auto air dump and manual.

[bpassmore]

My 1998 Disco runs at 135 when trucking.
If I do not flip the auto ride off, it will hold that pres indefinately.
if i flip AR to off, then if bleeds down quickly. (probably less than a min)