Trailer lost Tandems

no they will only release if you pull the release button the tandems when the trailer brakes are set.. as soon as you release the trailer tandem brakes the pins automatically reengage, i always do a small tug and visually make sure they have set..

 

Yes it was a summit truck the trailor was in the median till wendsday that i know of.

 

Looked like a Watkins Shepard truck...

 

Once you're spoiled with air slide you don't want to go back.

I have had a couple trailers that the release button wouldn't pop back in on it's own after disengaging the brakes. I always pop the red button a second time and tug to make sure.

 

OK we need to go just a little further into what holds the trailer together back there!

I won't count the number of times "PTI" was mentioned BUT a PTI doesn't always catch a bad or broken spring as well it's not part of the PTI! Just looking at the pins isn't enough.

If the spring breaks as you're going down the road and the bouncing works the Pins loose and the brakes are applied at even 30 MPH all the welds at the back of the trailer and the ICC bumper is not going to hold that trailer together! One of those laws of physics is applied and Newton ain't going to argue any fine points with you when all is said and done!

That part is now covered!

Lets start at the beginning of the "sliding the tandems" evolution:
You go back and pull the handle and you don't do anything but pull the muscles in your back because they're in a bind, so you go back and put the truck in gear and try to "loosen" the tandem on the rails or get the trailer to slide a 1/4 inch to loosen the pins.

Did you happen to notice how the trailer came up a little? NOT slide but physically climb into the air? Maybe almost off the air bags? Ever see another driver do this? I bet you have!

Most of you do but you are missing something that's NOT covered in a PTI!
Climb out and go back and look down the rails and you'll notice what looks like a "P" clamp. There are 2 of them on both sides of the tandems that has one bolt in the tandem and the clamp goes over the bottom edge of the rail. See them? Do they look snug to the top part of the bottom of the rail? If this trailer is a few years old maybe not especially if it's been hard to slide.

Here is a seldom known fact.
The pins are NOT what holds the trailer to the tandems! It's those 4 clamps! They actually all work together! The pins keep the two from sliding but the 4 clamps hold them down.

I watched a driver actually pull the trailer off the tandems while trying to break the thing loose! Oh, he got stopped before the trailer was on the ground but it was still a fun time for the wrecker crews!

During a PTI for me after learning something no one had shown me or written about until I had been driving almost 15 years was how the trailer was assembled! His demonstration helped me learn this!

Now when doing a PTI I look at those clamps. If they are NOT snug and tight to the top of the rail I will write them up. There should not be more than 1/4 inch of a gap between the bottom of the "P" and the top of the rail. Go look at a brand new trailer and notice the difference of how it looks to a trailer that's got a few years on it! If that clamp is looking more like a explanation point than a question mark or P it's time to replace them!

Also use caution when "checking" the pins with a tug.

If you pull so hard that the trailer pulls into the air you're putting to much pressure on those clamps! Yes the pins are in but they aren't setting in those loose holes tight enough to hold against the locking forces generated when those brakes come on at speed because those clamps have been bent out of shape and are suffering from metal fatigue!

Use some kind of device to help you pull those pins instead of slamming them with those 500 horses in the engine! You're just looking at what your future holds in store for you in what see in the video!

Anyway sliding tandems isn't the brute force exercise many drivers use to get those pins to unlock or the trailer to slide on the tandems!

Be gentle, use water to wash dirt out from between the rails and tandems or some WD40 (way to expensive!) but wash any oil or petroleum product off as they attract dirt and dirt can help to make it hard to get the trailer to slide.

Also slide the tandems when empty before loading to break them loose.
There is a thread about sliding tandems and some good ways to make it easier one by yours truly!

 

those little clamps you talk about ,only hold the the trailer to the tandems while the pins are disengaged--when the pisn are engaged they are what holds the trailer to the tandems
when you go to slide your tandems--dump the air if you can--this will stop the trailer from riding up on the air bags, and the truck perfectly straight to the trailer and a slevel as you can get it

 

i was able to get the phone number from the side of the other trailer, that was there for the load, and it was Cannonball Express out of Omaha....

the other trailer, the wreck, i could not see either...

 

What loosens those tandem clamps are running curbs.

Forcing one side out further and further till they barely hold.

Noticeable on dog tracking trailers.