How much air does your truck leak?

[jjoerger]

Air leaks drive me crazy. I have probably washed the underside of our truck with a spray bottle of soapy water looking for air leaks this last year. The last one I found was the fitting on the air line to one of the air gauges. I heard it while changing a dash bulb.

Since I am at home and the truck is not being run I have noticed once again I have another small leak somewhere. I am losing around 40-50 pounds in 24 hours. This is only 2 pounds per hour so it has to be another small one somewhere.

So my question: How much does yours leak?

 

[Dakota]

Air leaks drive me crazy. I have probably washed the underside of our truck with a spray bottle of soapy water looking for air leaks this last year. The last one I found was the fitting on the air line to one of the air gauges. I heard it while changing a dash bulb.

Since I am at home and the truck is not being run I have noticed once again I have another small leak somewhere. I am losing around 40-50 pounds in 24 hours. This is only 2 pounds per hour so it has to be another small one somewhere.

So my question: How much does yours leak?

No leaks that I know of but mine is a 2011 with 15k on it

 

[Mdbtyhtr]

I used to use freon in the line right off of the compressor and a freon leak detector to find the nuisance leaks. Sometimes they are a screw into a plastic line headed to an air horn, behind the interior trim. Sometimes they are hard to hear and the leak detector works great!

Scott

 

[greg334]

I had to correct a lot of leaks that popped up when I took the air dryer and dash apart, I still have to tackle rebuilding the parking brake valve some time in the near future.

The biggest leaker I found was the treadle valve, followed by the gauge connections and then the leveler valve in the back. The other location of leaks were the drain valves on the tanks, they got gummed up from the air dryer crapping out on me.

The treadle valve I rebuilt, if you never worked on these things, just get a rebuilt and replace it if the truck has over 500k on it. It can be a small leak that is almost undetectable but when it goes, your secondary air leaks a lot, the valve will continue to work by the way. What happens is in the valve there is a square O ring at the end of the valve that operates the secondary air to the brakes which gets hard and actually gets chipped away, easy to replace with the rebuild kit but unless you have the right tools and especially the right grease (expensive!), replace it with a rebuilt.

The gauge connections can be bought at Napa, bring the old ones in with you but a warning you may have to cut them off - remember which is primary and secondary.

The leveler valve for the air suspension is an easy fix, replace the fittings too.

If you are mechanically inclined, replace the air dry carterage(sp?), the AD-9 which is comment is only ~$75 from Napa rebuilt.

 

[bluejaybee]

What happens is in the valve there is a square O ring at the end of the valve that operates the secondary air to the brakes which gets hard and actually gets chipped away, easy to replace with the rebuild kit but unless you have the right tools and especially the right grease (expensive!), replace it with a rebuilt.

Why can't I picture a "square O ring"! hehehee!

I can park my truck on level ground and not lose any air overnight. Park on a slight slope and the leveler on the rear axle leaks my pressure down a little overnight. If truck sits like a week (heaven forbid) it will leak down to just where alarm goes off (55 lbs??). All the above places mentioned are possible, but really anything on your truck could be causing it. And that is the jest of it. I did the under the truck spraying before to finally find it at my air ride seat valve. So good luck.

 

[jjoerger]

Found my latest air leak today.
Since it is a nice warm 74 degrees I decided to crawl around under the truck with my soapy water bottle and found it within 3 minutes. I have a tiny pin sized hole in one of the rear airbags.
Air loss is around 50 pounds in 24 hours.
Time for a new air bag. At least it's a fairly simple fix.