Need stronger brakes, what can I do?

[LouNY]

When I was driving double deck truck and trailer back in the early and mid 70's most of the road trucks did not have front brakes.
When I started driving in the 60's some of the older stuff then was air over hydraulic, when it worked right it was better then straight hydraulic.
Most of the newer road trucks are using air front disk and many have optional rear disc brakes.
Better braking and lower maintenance costs.

From the DOT;
Trucks or truck tractors having three or more axles and manufactured before July 25, 1980, are not required to have brakes on the front wheels.

 

[ovrszd]

When I was driving double deck truck and trailer back in the early and mid 70's most of the road trucks did not have front brakes.
When I started driving in the 60's some of the older stuff then was air over hydraulic, when it worked right it was better then straight hydraulic.
Most of the newer road trucks are using air front disk and many have optional rear disc brakes.
Better braking and lower maintenance costs.

From the DOT;
Trucks or truck tractors having three or more axles and manufactured before July 25, 1980, are not required to have brakes on the front wheels.

Thanks for the technical answer Lou.

 

[North to Alaska]

You still have to buy the pump and other accessories, pay tax and shipping, putting total cost upwards of $2000. Not knocking disk brakes at all. But, Dexter axles and drum brakes are very capable. If they are not doing the job, it is time to troubleshoot.

My bad, you are correct about the pump.

 

[BWSwede]

Hello all,

I am the OP and am providing a follow-up to the posts I made last May regarding my trailer brakes. Thank you all for the great input that was provided.

When I pulled drums off the truck I found that the shoes and everything else in that area had a very light coating of dirty grease, almost like it had been deposited by a grease vapor. The shoes were also glazed over.

I replaced everything inside the drum with a new assembly on all 4 wheels. I adjusted the brakes as I always do, so that there is a very light rubbing as the wheels are turned. The rubbing is so light that it only rubs on the high spots on the drums (doesn't rub over the entire rotation of the wheel).

I loaded my tractor and made a run to one of the only two locations I haul my tractor. I know these routes extremely well and can even predict where the truck is going to shift. Over the course of the trip with the new brakes I felt that I had a loss of power the entire way. The only thing I could attribute it to is the brake drag. As this was occurring I recalled the truck having a lot of power over the last couple trips to this location prior to the brake job. It was during these trips that I also noticed my trailer was not stopping as it had in previous years.

This leads me to my question. Do I have to choose between what appears to be truck power (I realize this is a constant) and the ability to stop my trailer safely? Could it be that glazed brake shoe causes very little drag on the drum versus a new shoe when the brakes are not actuated? Should I back off my shoes so that there is no rubbing at all when not actuated?

TIA,
BWSwede

 

[4570Man]

If the brakes are really adjusted so they barely drag by hand there should be no loss to power. Maybe try jacking it up again and make sure they didn’t settle in tighter.

 

[zzvyb6]

Just in case someone doesn't know, electric brakes don't help stop the combination because of the electrical energy supplied to the axle(s). They work by utilizing the self-energizing feature of the drum brake design. Once the shoes get a signal from the magnet levers, a small amount of shoe friction drags the shoe assembly into a wedging situation which cause the shoes to press even harder on the drums. Unlike disc brakes (no self energizing mechanism) the 'Q' amplification factor is very large.

However, if the shoe assembly can't move or moves in the wrong rotation direction for the added clamping force, then all you get is the electric brake supplied pressure, not the friction driven force application. Some types of drum brakes only work in 1 direction.

So is the axle mounted backwards ? Can you lockup the trailer wheels when backing up only ? If so, this needs to be changed.

 

[SPYDERLK]

Just in case someone doesn't know, electric brakes don't help stop the combination because of the electrical energy supplied to the axle(s). They work by utilizing the self-energizing feature of the drum brake design. Once the shoes get a signal from the magnet levers, a small amount of shoe friction drags the shoe assembly into a wedging situation which cause the shoes to press even harder on the drums. Unlike disc brakes (no self energizing mechanism) the 'Q' amplification factor is very large.

However, if the shoe assembly can't move or moves in the wrong rotation direction for the added clamping force, then all you get is the electric brake supplied pressure, not the friction driven force application. Some types of drum brakes only work in 1 direction.

So is the axle mounted backwards ? Can you lockup the trailer wheels when backing up only ? If so, this needs to be changed.

Good points for sure, but I think he is referring to a change/rebuild of his truck brakes, which now drag.​

 

[jasonzee]

I have to change the brakes on my 5 ton trailer this summer.

 

[dodge man]

I also read your post at first like you were talking about your trailer brakes on yesterdays post. Your truck brakes or any drum brake should not drag. Are they hot after you drive? Almost all newer drum brakes on vehicles, I知 not sure about trailers, are self adjusting. This happens when backing up. Back up a long distance somewhere and that should adjust them out. If not something is wrong, weak springs, not put together correctly or the drums need turned.

The other problem is where did the grease come from? Most likely a bad axle seal.

 

[ovrszd]

I'd do the "hot" test first to make sure it is brake drag you are feeling.

If so, I'd loosen them until you feel no resistance. Then let the self adjusters do the fine tuning. Understanding that self adjusters only work when the brakes are applied. So, while backing up, apply the brakes. Each time you repeat this process they will tighten one "notch" until they can't quite catch the next notch. The idea being that they will maintain a certain tightness