• Thank you for visiting HeavyEquipmentForums.com! Our objective is to provide industry professionals a place to gather to exchange questions, answers and ideas. We welcome you to register using the "Register" icon at the top of the page. We'd appreciate any help you can offer in spreading the word of our new site. The more members that join, the bigger resource for all to enjoy. Thank you!

Trailer air brakes

Joined
Nov 24, 2020
Messages
17
Location
Seneca Kansas
I have a 2012 wilkens walking floor trailer, we have put new drums, and new shoes on it and even after adjusting the brakes will not hold a loaded trailer. Any help resolving this problem would be appreciated.
 

Pops52

Senior Member
Joined
Jan 19, 2016
Messages
294
Location
Penn Valley, CA
Occupation
Worn out lowbed driver "retired"
I have a 2012 wilkens walking floor trailer, we have put new drums, and new shoes on it and even after adjusting the brakes will not hold a loaded trailer. Any help resolving this problem would be appreciated.
Strange.... couple questions first. Has Automatic slack adjusters? It should have. 2 Are you experienced with this type of brake work? Is a picture of the brake shoes, drum, brake pot and slack adjuster with brakes released available?
 

Jonas302

Senior Member
Joined
Jan 4, 2015
Messages
1,198
Location
mn
When you say hold a loaded trailer are you talking parking brakes ? If so the springs may be broken in your brake cans take the rubber plug out shine a light in for a look run your finger in the spring checking for breaks given that they still rely on the foundation brakes to be in good working order have someone apply the brakes and measure the stroke, look for wore s cam bushings brake can mounts rusted and flexing
 
Joined
Nov 24, 2020
Messages
17
Location
Seneca Kansas
Strange.... couple questions first. Has Automatic slack adjusters? It should have. 2 Are you experienced with this type of brake work? Is a picture of the brake shoes, drum, brake pot and slack adjuster with brakes released available?
I does have automatic slack adjusters, I have done some brake repairs, but I'm no mechanic. I have done some further trouble shooting, and 3 of the S cam shafts have some play in them at the bushing, could this be the problem? Everything else seems to be working properly.
 
Joined
Nov 24, 2020
Messages
17
Location
Seneca Kansas
When you say hold a loaded trailer are you talking parking brakes ? If so the springs may be broken in your brake cans take the rubber plug out shine a light in for a look run your finger in the spring checking for breaks given that they still rely on the foundation brakes to be in good working order have someone apply the brakes and measure the stroke, look for wore s cam bushings brake can mounts rusted and flexing
Yes, the parking brake does not hold, stroke is good on all of them, however there is some play in 3 of the bushings, not major, but some. We are thinking this could be the problem.
 

Jonas302

Senior Member
Joined
Jan 4, 2015
Messages
1,198
Location
mn
Will the trailer hold with the jonny bar on the brakes? If it does it would confirm the springs being broken
 
Joined
Nov 24, 2020
Messages
17
Location
Seneca Kansas
Parking brake side of the brake chambers is more than likely bad. Moisture, and dirt will cause them to
rust the killer spring inside and eventually it breaks. Average life of a brake can is 4 to 6 years and those
start to fail.
I will check that out, but just wondering, will the brakes look like they are working with a spring broke?
 

Shimmy1

Senior Member
Joined
Aug 14, 2014
Messages
4,320
Location
North Dakota
Need pictures of each brake chamber, brakes set, released, and applied with the jonny bar. Needs to show axle, slack adjuster, and s-cams.
 

Shimmy1

Senior Member
Joined
Aug 14, 2014
Messages
4,320
Location
North Dakota
What for? those air chambers are more than likely original equipment. 11 years old.

We have trucks and trailers that are almost 20 years old, and have never had to replace a chamber due to a rotted spring. Not saying that isn't his problem, but I'd sure as heck be verifying that he has the slacks properly adjusted before assuming the chambers are shot. By his own admission, he says he isn't a mechanic.

I have done some brake repairs, but I'm no mechanic.
 

Truck Shop

Senior Member
Joined
Dec 7, 2015
Messages
16,898
Location
WWW.
Really when it comes to brakes unless it's a hands on inspection-all the advise is pretty worthless including mine.
2012 should have auto slacks and unless he measuring the stroke we won't know because there is no camera
that will perform that.

And one real big fact unless the OP or anyone else on here is brake certified and carrying a
{Brake Inspection Certification Card as required under mandate 396.25 section 3{A} as described within the federal register. They can't even touch a air brake system-can't even adjust them. So it's hands off for everyone.

But I have been trained and updated to cover all air disc and carry a card.
 
Joined
Nov 24, 2020
Messages
17
Location
Seneca Kansas
We have trucks and trailers that are almost 20 years old, and have never had to replace a chamber due to a rotted spring. Not saying that isn't his problem, but I'd sure as heck be verifying that he has the slacks properly adjusted before assuming the chambers are shot. By his own admission, he says he isn't a mechanic.
A couple of the chambers have been replaced, I am not a mechanic but I do know how to adjust the brakes, and they are properly adjusted. They are automatic, but I have found that even these need adjusted ocassionaly, but I don't like messing with the chambers, or s cam bushings, the boss has decide to take it to a shop. Thanks for all the responses, I appreciate them.
 
Joined
Nov 24, 2020
Messages
17
Location
Seneca Kansas
We have trucks and trailers that are almost 20 years old, and have never had to replace a chamber due to a rotted spring. Not saying that isn't his problem, but I'd sure as heck be verifying that he has the slacks properly adjusted before assuming the chambers are shot. By his own admission, he says he isn't a mechanic.
Our trailer hauls garbage to a landfill, so they take a lot of mud, and other debris, 2 of them have been replaced, but not recently.
 
Top