How do you adjust the trailer brakes?

When backing off, sounds like it’s being destroyed. Perfectly normal.

 

I think every Driver should be trained in brake adjustment. It’s in their own interest. No way of knowing if a trailer you’re picking up has a problem till it’s too late. Keeps everyone out of trouble. No different than airing a tire, changing a headlight, wipers, mudflap. Beats wasting time in a shop, losing money for the day.

 

Yes, because it’s hard on the ratchet. If they won’t ratchet properly simply using air pressure then the slack adjuster is faulty.

 

How many trucks have pressure gauges these days?

Mine don't.

 

Years back, when I was still very new, I was responsible for the maintenance on the truck and trailer I ran. I used the same trailer all the time, it was the only one we had.

I'd learned the basics of adjusting brakes, through my dad and my uncle. But I was taught on manual slack adjusters. Never saw an automatic slack adjuster until I was handed the keys. I didn't know what the heck I was looking at, and adjusted the brakes the way I was taught. And they were fine- for a while.

One day me and another guy made a trip for two loads of equipment, on what should've been a one day trip. A fire and a snowstorm later, we ended up camped out in a rest area for the night. Next morning we wake up, head to the nearest truck stop for breakfast.

The restaurant was at the top of a hill, and we parked right where the level part started going downhill. We go inside and we're eating, he's facing the window and my back is to the window. After a bit, he's taking a sip of coffee, he spits it out, asks 'is that your truck at the bottom of the hill in the ditch?'. I turn around and look 'sure is' and bail out the door. The truck slid down the hill into a small ditch. Didn't damage anything thankfully. But I realized there was something wrong when I looked at the tire marks.

Evidently, my truck brakes were way out of adjustment. It freewheeled down the hill, with the trailer wheels dragging in the snow.

After limping it home, we replaced all the slack adjusters, I got a lesson on how to adjust and maintain them, along with a memory I'll never forget.

Now about 20 years later, everytime I see the other guy, we always laugh about that trip form hell.

 

The release and application of the foot valve let the mechanism catch as the slack traveled too far and it managed to adjust.

The trailer parking brake spring has limited travel and depends on proper adjustment to hold so unlike an application of the foot valve it can't 'catch' and operate the mechanism that does the adjustment.

 

Not so much limited travel, more limited pressure. Quite often as they age, the springs reduce in spring pressure.

 

What do you think?
If I were management it would be very likely they would be fired. You don't just let Billy Bob play with brakes. This gets people seriously hurt, killed or sued. It can't be tolerated unless that driver has a VERY verified history as a COMPETENT heavy truck mechanic, not just a drinking buddy's nod. I would not let that fly. Now, if the driver wants to crawl under there and take a visual because he thinks something is wrong, by all means. Go take a look.