Did that. No dice. You would think I could hear it but I can't. That's why I was kind of thinking the glad hands in the back. If not...I am going to have to resort to soap and water. I know that the air compressor is putting out 120 psi now, even at idle. I thought in another thread that maybe because I had left the windshield wipers on high, that that was the problem. I have them completely shut off and no leaks...I checked. I started it up and let it build full pressure, then shut it off. Crawled under and around the entire truck and cannot hear a leak. Funny thing is, as I drive it and use the brakes, it doesn't seem to drop air pressure that much....certainly not enough to give a low air pressure warning, as long as the engine is running. Right now, I am getting my house fixed up to sell, and working during the week, so I am going to have to try to take a closer look on Saturday. I will post what I find. If I don't find anything obvious...I am going to crack open the TMs.