Since you asked about lowering via HR or Eibach - I am guessing you only have self leveling suspension in the rear.

NOTE - the air tubes are next to the battery cables under the cargo compartment, I wouldn't go spraying any soapy water down there.

Take out the spare tire and listen / feel for air leaks after starting the truck. I would bet the actual leak is the pneumatic spring. I just replaced my spring and it's pretty easy. Search for my write up a few days ago.

RE springs. I used the Eibach springs with Dinan camber plates and can't believe how much better the truck handles.

Good luck Eric in AZ

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