Anyone have issues with volvo air manifold above driver fuel tank?

This should go to the Volvo forum. You will get a lot better information on it. I have never had an issue with that on my 2014 and 2023.

 

Try pulling the brass collet off and flipping the O-ring around or replace the O-ring.

If you just replaced it, it will have a one year warranty.

 

There is a way to fix it so it won't ever leak again.

 

How? I’ve replaced two in the last few years. They aren’t cheap.

 

Probably bypass them all with a bunch of compression tees and elbows. I'm guessing there are no internal valves and it's just a distribution manifold.

 

There's internal ports.

 

I replaced them on 3 trucks, started leaking again.

Plastic line for all the ports.
Compression fittings for each line.
Stub a 1" line on compression fitting
Super glue gel inside and outside of plastic line and shove in port.
Now the whole block has compression fittings.

 

Pull out leaking line and check the tube end cut. It should be cut 90 degree clean. If end has some wear cut it with razor blade. Insert tube all the way in port and pull locking lock out slightly to lock tube in place.
The manifold is to supply air for auxiliary things - cab suspension, diff lock, fifth wheel slide, rear air suspension bags. Nothing to do with brakes. If system pressure falls below 20 PSI valve in the manifold will close supply.