Tandem Release Pins

Picked up a trailer last week and needed to move the tandems. Wouldn’t budge. I had to beat all four pins to within an inch of their lives to get things to slide. Do these mechanisms need periodic maintenance? When we get a trailer like this should it be reported for maintenance? I’d hate to think every driver who got this trailer was going to have the same problem

I carry a can of lubricant and a big hammer. When they don't retract I spray them and I pound the hell out of them I've never had them fight back... LOL and yes you should report this to the maintenance department. What I have found to happen is you might have to drive a ways to get the airlines fully functional and then the pins will retract. I will sometimes drive a few hundred yards stop and apply the trailer brakes. Winter time is the worst. Don't have a lot of problems when it warms up.

Yes, the big hammer and WD-40 come in handy.

One other thing to try is to move the trailer on the tandems just like you're making the adjustment but without pulling out the pins. Maybe a pin is stuck against the rail and needs to be moved away just a tad.

Junkyard K9,

Thanks for the input. I didn’t know the release mechanism was pneumatic. Are all trailers like that?

Just a side point, if I have to hammer on the pins, I start out with my 2 lb. hammer, but to get them fully retracted I need to finish the process with my standard hammer because the hammer head needs to be smaller than the pin itself. Thankfully this doesn’t happen very often.

What often happens is what Errol mentioned - the pins get jammed against the rails. That happens two ways:

1) Applying the brakes hard will jam the pins against the back of the hole

2) Turning the trailer very sharp in a tight circle, like when someone does a tight spin in the parking lot, will twist the tandems and jam the pins on one side of the trailer against the front of the hole, the other side of the trailer against the back of the hole.

If all 4 pins are stuck it's almost certainly because of one of those two circumstances. When they're stuck, take a moment to look at all four pins and you'll normally figure out why they're stuck and you can free them.

If they were stuck from hard braking you can keep the trailer parking brake on, put the tractor in reverse, and push against the tandems to get the pins recentered in the holes.

If you can see one side is stuck against the front of the hole, and one side against the back from a spin, then I would normally keep the trailer brakes on and pull on the tandems, then push on them. Do this a couple of times in each direction and it will get the twist out of it.

In both cases you might have to play around for a couple of minutes. You might jam the pins too hard against the front or the back of the holes, so just keep pushing or pulling on the trailer until you get them centered and the pins will pop out easily.

I most always spray the pins when I grab a new trailer, unless it's going to a quick drop. Makes it easier down the road to slide the tandems at the dock. There will still be times of pin non-compliance, necessitating a beating. Breaks my heart to resort to the pry bar and hammer!

We do not have pneumatic release pins. Our older trailers have the wrist breaking bars. You have to lift the bar to release the pins. If you grab it with your hands and pull up and the pins release, your forearms will slam into the bottom edge of the trailer and at best leave a bruise. When these are stuck a 4 foot piece of pipe will sometimes help. If that doesn't work, 2 long bungee hooked to the trailer support beams and under the bar will keep tension on the bar. Then a good hard rock back and forth should release the pins. Our newer trailers have a round bar that you pull out and lock into place. Once it's out and locked, if the pins are locked, a good hard rock back and forth should release those pins. No beating required.

If your trailers have manual release handles, be sure to carry a pair of vice-grip pliers to hold the handle out in cases where you can't get the thing to stick in the notch.

If you have air-release pins, in addition to what has already been mentioned, note that you may need to give the trailer a couple of minutes to air up with the trailer air supply knob pushed in. Pretty rare that you really have to beat them in

Picked up a trailer last week and needed to move the tandems. Wouldn’t budge. I had to beat all four pins to within an inch of their lives to get things to slide. Do these mechanisms need periodic maintenance? When we get a trailer like this should it be reported for maintenance? I’d hate to think every driver who got this trailer was going to have the same problem

Vice grips are handy. I also carry a husky brand mini sludge from the home depot. Heavy, but not so heavy you can't get a few good whacks single handed per pin. Works well.

I have hauled some old rusty POS Swift trailers in the past. NEVER had to beat on the pins. Im with the release the pins and rock the truck crowd on this one. I think you may have hammered the S#*! out of them unnecessarily.