Trailer brakes locked

Question for you. How good are your mechanics and did they recently work on this trailer? It sounds like a distribution valve to me and I think the tanks on some of these units have to be pretty well filled before the tag axle will raise.

Hope you get it fixed.

 

Now this went way over my head!

Brake adjustment really doesn't matter if loaded or MT! Yes a lot of owners like to use the trailer brakes to save their brakes from wear but if they are smart and when stopped use their tractor brakes the trailer should self adjust if done properly. But loaded or not makes no difference on self adjusting or manual slack adjusters. They adjust to a certain length or "turn of the adjusting nut." BUT, if the brakes are adjusted properly or a little over tight, then when MT oh yeah they'll "lock up" and that trailer is going to go bouncing all over the place if you hit the brakes to hard! But to be locked up when setting then it's a low AP problem.

Now if this were that above quote were true then there would be an awful lot of trucks put out of service with out of adjusted brakes! Heck the DOT would be sitting outside the gates of every receiver in the country making money for the county that way! Not to mention the "road side mechanics" with only a handful of combination wrenches and a screwdriver in their hands riding a bicycle back and forth making killer money off of truckers!

Now the air in the bags are adjusted by weight. The more weight the valve rod pushes the valve for more air. Take weight off air is released.

The locked brakes can be telling you that there is no air getting to the brakes. Remember we use what technically used to be called 'reverse action" brakes or take air away from the brakes they activate. That's why when your AP drops below... OK TEST TIME!! WHAT pressure does the emergency brakes activate at? LOOK HERE for the answer if you don't remember, §393.43 It doesn't matter if there is air in the tank if the brakes are not activating but if the air pressure goes down when the brakes are pushed then the valve is bad. Time to replace.
That's the best I can tell you.

Brakes are actually easy on the trailer. It's in the dash and floor where they get to be a PINT!

 

My cousin did the "burn the companies" trailer brakes until he caught them on fire half way down Cabbage. When the fire was out his father (My Uncle) an old trucker himself caught a ride to the bottom with someone else. And when he got back in the truck with his son, they had a little talk.

 

I can just imagine that little talk! More like biting big chunks out of the portion of the body that contacts seat! That's why there is that foot pedal on the floor! All 5 sets are better than 2 because when 2 are smoking and fading the remaining 3 aren't that much good, which screws up that idea of just wearing out the companies trailer brakes and save the owner operators brakes. The tractor brakes are gonna get a tad bit worn worse that way than using them all on the way down! LOL , But what do I know I'm just a driver!

 

Get a glad hand and a pipe cap that will thread into it, put it on your red line, push your red handle in, if your truck holds air pressure the problem is in the trailer somwhere.

It could be anything form a glad hand not sealing right, to a piece of garbage that is blocking an airline.

It could also be that your valve on the trailer is bad. I have seen this happen before, I had a lot of headaches with it, trailer I was pulling would lock the brakes up going down the road, you would pull over, and then everything would befine, then it would do it again a few hours down the road.

Swapped out the valve on the trailer and never had another issue.

It was a phantom problem for quite a while.