Experienced Opinions Needed - Tire Issue

So after sitting 10 hours to get my tractor brake chamber replaced, I had to swap my load this morning. Got hooked to new load, the other driver comes back said we have a problem.

I had 2 flat spots on my tires. I’ve had the trailer 2 days, so 2 pre and 2 post trips. Had not pretrip per today as so had just woken up.

Truck brake chamber should not affect trailer brakes, correct? I was barely able to maintain enough air to keep the buzzers off, but they are separate systems, correct? I had no hard braking, nothing I can think of except a stuck tandem pin but that was maybe a foot or two at most of dragging.

I can’t for the life of me figure out how one set of tandems got a flat spot, but the other 6 are fine, and without me noticing anything like a locked up brake or something.

Any ideas?

Did breaks lock up, even for a short period of time, this could have done that while dragging tires...

Did breaks lock up, even for a short period of time, this could have done that while dragging tires...

Just saw u didn't notice breaks lock up...🤔🤔🤔🤔

Likely on the wheel where you had the bad chamber?

Likely on the wheel where you had the bad chamber?

Chamber was truck, tires are trailer

The spring brake engaged on that wheel at some point.

Air must build up in the entire system in order to have sustained pressure necessary to release and hold the springs in a released state. If the spring brake in that wheel was not adjusted and/or worn, it might have “set”, while the other three had enough pressure to maintain their release. You dragged this wheel around for a bit (obviously). I am not a mechanic, however that is the only logical explanation I can think of based on the information you shared.

One question though...

Why did you move the truck when you were unable to maintain safe pressure? Hopefully it wasn’t very far and not on public roads.

I'm not an expert on brakes by any means, but if the air pressure was low I could imagine one wheel locking up, since it would depend on the weigh on it, the traction, the condition of the brake pads, etc. So maybe that wheel locked but the others were just dragging the brakes.

As for the truck problem affecting the trailer, I guess maybe since there's only one compressor, if it can't pressurize the truck system because of a leak it probably can't add pressure to the trailer either. I think there are check valves so that if part of the system has a leak then other parts will maintain pressure to allow you to stop, but eventually you probably lose pressure to the whole system.

Lol, this time g-town's the speed typer. He posted his while I was writing, didn't mean to repeat what he said.

Lol, this time g-town's the speed typer. He posted his while I was writing, didn't mean to repeat what he said.

Too funny. No worries.

I’ve noticed trailer brakes are more likely to lock with no weight in them, an empty trailer. If you’re not really closely looking at all tires several times each day, things like this are going to suddenly pop up at the worst times.