I knew I had a leak somewhere because my auxillary compressor kicks on about every three hours. This evening I had some time so I started searching for the leak. First spot I checked was the steering compartment where there are so many air connections, and proving the old saying that even a blind squirrel finds a nut now and then, there it was. Looks like the Norgren valve has a small crack. Does anyone have the NAPA replacement part number for these valves? I think I will go ahead and replace all the easy ones.