Air leaks!!

I use Super Lube silicone grease for o-rings, but I have come across several instructions where they say you can use fresh engine oil instead.

 

My leaks where coming from the tanks under the driver door. I almost never found em. Good luck

 

Also make sure that the tip of your hose is straight and clean.

 

I had one problem air leak that I chased for a while. It started off slowly leaking down overnight and then the suspension leaked down in 30 minutes, but not the air tanks. I figured it had to be in the bags somewhere even though they had been sprayed several times. Finally after completely soaking the bad air bag the leak showed itself.

 

Take the truck to a quiet place and listen closely. Also, check your air guage and see how many pounds per minute the pressure drops. If you are loosing air at a decent rate, you should definitely hear where it's coming from.

 

Automotive stethoscopes on Amazon are cheap, find a quiet place than listen . Took me a while to find a air leak, it was coming from on top of transmission and was a $15 fix .

 

Did brakes awhile back and while at them replaced all the valves (QR, relay etc) except treadle. Truck would loose air parked overnight. While doing the valves, I felt I was foolishly wasting time and money. One of those rare projects that exceeded my expectations. Gauge doesn't move sitting overnight. Park the truck when roads have been wet and crappy and it is going to be very cold overnight can leave brakes released with no worry of shoes froze to drums etc. Much easier to pick up choke blocks in the AM than to worry about frozen brakes.