Tandem pins will not retract, lack of air pressure?

I know exactly what you are talking about. When you pull the knob you will hear a tiny little puff and then nothing. Maybe the pin will move a tiny bit inwards then stop.

All it you got to do is push in the red air knob for your trailer and wait a few minutes for the trailer to fully air up. It is even a longer wait if you have those auto inflating trailer tires, because now you got to wait for those too to air up.

Sometimes the pull lever for sliding tandems on older trailers is a blessing to have. Simpler times.

 

When you hook a trailer check fifth wheel locked, raise landing gear, connect glad hands/ pigtail. Get back in truck turn on your lights, flashers, and PUSH IN RED BUTTON. Walk around truck inspecting lights, tires and listen for air leaks. After a few minutes there should be adequate air pressure to open tandem pins. If not wait. If waiting doesnt work try tapping stuck pin with a hammer.

 

Yup. Rock a couple times and pins slip out.

 

Are we dealing with trailer tandems that slide? With a air release mechanism instead of the old school 4 foot iron arm breaking bar to pull the pins? Sometimes a little bit of pin and sledge hammer work to punch the pins in if it is crooked.

Or are we dealing with the much more common tractor 5th wheel air release to slide it forward and back?

You do not want any flaws to leave that 5th wheel unsecured. I once came off the tydings bridge on 95 south in Maryland with a ford 9000 daycab and the 5th wheel threw the trailer clean out after it took that hop in the suspension. Fortunately for all involved the container was empty and came down on the second set of drive tires to roast and burn until we got it stopped to jack it back and rehook. There were so many cars around us that night.

 

On my buddies' reefer I pulled, sometimes they wouldn't retract completely but weren't binding in the holes. I just scurried under there and moved them the rest of the way in by hand. Have you even crawled underneath?

 

I should stop getting underneath, I keep trying to lift the trailer with my head.

 

USE with caution when it doesn't want to slide due to rust ice buildup etc I use visegrips to hold button out and hit the spike while rolling to get things moving works also when ground is icy.. Please remember to remove visegrips

 

Mine will keep the button out and only works when red button is pulled. As soon as red button is pushed in it forces the pins outward into locking position again. Vanguard special lol

 

I don't know much, but when my trailer had this problem the mechanic replaced the rubber o rings inside the valve button and it fixed it.

The trailer requires air to retract the pins and to push them out. This requires a good seal at the valve. Just like a leaky faucet, the o rings go bad.

 

And just to clarify, trailers are different between manufacturers. On Great Danes, you push IN the "button" to release/retract the pins and the only way to get the button back "out" is to supply air back through the red hose (release trailer brakes)