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Air ride leveling valve problems

20096 Views 23 Replies 10 Participants Last post by  jgbutler2004
Well, I posted this once before, but was recent enough the thread was lost in the mess.

OK, here's the deal. The dump valve was replaced last year (by someone else, so I don't know what they did), but things haven't been right since. The bag fill like they are supposed to, but, don't unload the air bags like they should. The valve exhausts air, but the suspension doesn't come down like it should. Just likes to drain the air tanks.

Switching the air flow on the "in" and exhaust ports doesn't help. Not sure if swapping the long screws to turn it 90* in the bracket will work or not? Taking the other one apart, I don't think so.

The new valve is no different.

Any ideas?

'95 Mack CH613. Almost 1 million miles on it.
21 - 24 of 24 Posts
where is your dump valve located it needs to be bewteen leveling valve and bags if its not and its before your leveling valve yo will just drain your tanks
The OEM location on this truck has the dump valve BEFORE the leveling valve. Worked fine til the leveling valve was changed.

Haven't been around to even look at, or mess with it.
but it mght not be the right valve and there for dump valve needs to be after the leveling valve
The one we have reacts plenty fast. It just empties the air tanks, NOT the air bags like it is supposed to. :bang:
There are two different types of dump and leveling valves Constant open and Constant closed. Make sure they both match eachother. You may have a Constant open dump valve with a Constant closed leveling valve for example
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