Trailer Brake Problems
 

Last week I took my boat down to Florida. Everything worked great on the way down until just before I got to my destination. The trailer is a Ameritrail Aluminum trailer with tantem axels. Brakes on one axel. As I applied the brakes they would chatter real bad. Bad enough to bounce off the ground 6inches. Sometimes I could get through it by braking, as the chatter started, let off and brake again , then they would hook up normally. I pulled both drums to inspect. Everything looked great. No Grease, or brake fluid leaks, everything looked fine to the eye. I ended up disabling the surge brakes to get home. Now I need to fix the problem. Anyone have any sugestions on where I need to look?

Looking for hot spots in the drums.

Sounds like the drums are warped/out of round.

I will check into the drums in the next couple of days. Anything else I should be looking at?

I think you may have some air in the lines and as soon as you hit the brakes the air moves quicker then the fluid. You need to bleed the wheel cylinders and top off the master cylinder.

Air in the lines wouldn't do that. Air in the lines would compress and cause the brakes not to engage as completely.

You could have a brake line collapsing though. It would expand and let a bunch of fluid into the wheel cylinders and then collapse and not let the fluid back toward the reservoir as braking is decreased. Or it could be an obstruction in one of the lines. Since you don't say anything about pulling, I'm guessing it would be in the common line.

My trailer does the exact same thing when stopping when empty. Damn thing feels like it's going to tear the back of the truck off. Truck and trailer both bounce up and down like a mofo leaving trailer tires smoking. Doesn't matter if stopping from highway or traffic creeping speeds.

I've tried bleeding till it bleeds red. rebuilt the new master cyl, new coupler shocks. Nothing worked. Trailer shops are at a loss, along with Eagle. Census is the brakes are to touchy with no load.

My thought is that when you stop, the braking axle tries to roll forward and going thru the equalizer lever, it exerts downward pressure on the other axle, thus lifting the braking axle off the ground enough to where it looses it's traction. At that point, the coupler slides out, axle falls back down, brakes get reapplied and the process starts all over in only fractions of a second. I have disc brakes on all axles.
I had the wife pull the trailer forward at walking speed, then stop while I watched the coupler from the sidewalk. It cycled in and out with every bounce of the trailer.
I'm am installing EOH this very minute because 4 yrs of this chit, I'm tired of it.


Overlooked your condition. I gather it haapens even wiht the boat on your trailer?

EOH is the catz a$$! My only regret is not doing it sooner.

Yes mine does it with the boat on the trailer. I haven't had a chance to dig into it yet. Just trying to get as much info as possible. I should start working on it in the next few days.
Thanks for all the tips.

Some of the couplers have a small shock in with the master cylinder, And maybe that has went bad and allows the brakes to be applied too fast.?

The drums look real good. Think the problem might be up by the coupler. Going to check there next. It is an Attwood coupler.

I'd check the shock in the coupler as well, if bad will allow full compression to the brakes.

Is there a certain way to check the shock? How will I know if its bad?

The shock only dampens the braking. It doesn't control the coupler travel.

With the brake line either unhooked or no brake fluid, you should be able to move teh coupler in and out and feel the resistance of the shock working just as in your cars suspension.

My Ameritrail doesn't bounce when the brakes are applied, it just engauges real hard and on occassion will lock up the tire. Flat spotted two tires last year. Road side does it the most. I've tried running them loose and they hit too hard. I run them tight and it locks up . The shoes and everything are fine. I swapped drums side to side and no difference. Repaced the wheel cylinder, shock absorber in the tongue, no help. The line to the back is fine. About the only thing left is the master cylinder right? Let me know if you figure yours out. Ameritrail was stumped too.

I will be replacing one of the wheel cylinders in the next few days. Then bleed the brakes and try again. Everything else looks good as far as I can tell. Hope that fixes the problem. I will let you know.

Well I still haven't figured out what my brake problem is Yet. Here is what I've done so far: Like I mentioned earlier, I had replaced one of the wheel cylinders proir to going on my trip. everything fine for 1300 miles. Checked out the other wheel cylinder and could see a little rusty fluid under the boot so I figured I would replace that too. Also checked all brake lines. The brake line along the axle had rubbed on the trailer and was ready to rupture. That had nothing to do with the problem , but replaced that too. Took off the coupler and the master cylinder. Cleaned every orfice and replaced the gasket where it attaches to the coupler. Bled the brakes. Still have the problem. At this point I am sure it has nothing to do with the coupler, wheel cylinders or air in the lines. My next move will be to look into the brakes themselves. The coupler manufacturer said it has nothing to do with the little shock absorber in the coupler. I figure it has to be the drums, the shoes or the brake shoe springs? Monday I will pull the drums, take out the bearings and have the drums turned. If that doesn't work it has to be the shoes or the spirings. If none of that works, I think I will just shoot myself :drink:

Griff, If nothing above works I will replace the main brake line next. Thanks for the advice.

Which axle are the brakes on? I could see this being the case more so if they are on the front axle.

Have you checked for a warped drum?

The disc conversion is not all that expensive. Why not update? I have had drums on a few trailers in the past and nothing but problems. The catz azz is EOH if you are able to budget that.

Chec to make sure there is a small adapter on the master cylinder where the brake line connects. That is used to control the pressure in the brake sytem. Also, do you have leaf springs connected to each other or torision system? Leaf spring systems require all brakes to work equal. If unequal, they will cause a rolling of the axles and cause the wheel to loose traction. Also are the brake shoes on right? Bigger shoe to the back...........

On a diffenent note, the disc brake system is much better that drum. More if in a salty area. Much easier to flush. But must add the 5 pin connector for the back-up solonid.

Best of luck with this nightmare. And keep us posted..........

What are EOH brakes?

Electric Over Hydraulics

You replace the surge coupler setup with an electric pump. Uses an electric brake controller in your truck, same as a camper. When you hit the brakes, the controller sends power to the pump, which provides pressure for your hyd drums or disc brakes. There are so many good things about this setup. Only drawback is you can't tow your trailer behind any truck like a surge brake trailer.

I would like to upgrade to a disc set up someday, but at this time I am going to stick with the drum set up....I'll feel defeated if I give up now!

The brakes are on the front axle, No leaf springs, so I believe what I'm seeing is a torsion system. I have never had the brake shoes off and the big shoe is on the rear. Shoes have maybe 50% wear or less. I did check the orfice on the mastercylinder/brake line connection all looks good. The drums look good to the eye and I tried to measure them to see if there was any distorsion, but I realize the only way to know for sure is to put them on a drum lathe. I will get them turned this week and let you know how it goes.
Thanks to all for your ideas.

I bet the drums are warped/out of round. You may not notice it when they are cool but after driving they get hot and expand and make it that much worse. Being a torsional axle will really excentuate the pulsation. I did the disc brake conversion on my trailer and I can say it was the best money I spent on my trailer. The kit was $400 shipped to me. It came with EVERYTHING, including coupler. Just my .02

www.trailerpartsdepot.com

charlie

Alright, things are looking up. I finally found something wrong.
Had the drums turned today. Said one was perfect, one was Warped. Just so happens that is the same side as the wheel cylinder I suspected had a problem. Got everything back together and could not road test as it is raining. Probably get a chance to road test it on Wednesday. Got my fingers crossed. I'll let you know how it goes.

Good luck with the road test.

I took a road test tonight. 95% of the chatter seems to be gone. Most of the time the brakes hook up like normal. But once in a while It chatters about 3 times ,for about 1-2 seconds then grabs like normal. I'm not sure what else to do. Maybe the brakes have to burn into the newly turned drums to fit right? I am going to try it for a little while and see if it corrects itself.
When I had everything apart I just cleaned everything with Brake cleaner. My other thought is to sand the pads with coarse sand paper to de-glaze the pads. I also read in an old post that it might help to sand off the sharp edge at the end of the pads to keep it from grabbing too hard when the brakes are applied.

I've had this thing apart so many times I could problably quality for a Nascar pit crew member. Pulled the drums and sanded the pads with 36 grit paper to clean off the glaze. Also filed the sharp edges on the leading and following edges of the pads. Re adjusted the brakes and took it for another road test. Still chatters under light braking at first then hooks up. Under heavy braking it seems to work alright. I haven't took it on a long trip yet so I don't really know how it's going to react. What else could it be?

When I worked on brakes years ago, we turned to drums and then arc'ed (re-shaped) the brake shoes to match the new diameter of the drums. Maybe with move to disc brakes, this is a lost art.
Can the shop that turned the drums do this for you?

What did the finish look like on the drums when you pulled it back apart? was it smooth, if so then the shoes should be seated in. Also make sure there are no "chatter" marks in the drum form the refinishing. Sometimes if the lathe is not set up right, the bit will chatter and make a consistent pattern in the refinished area. More commonly near the outside edge. If these marks are there then you need to refinish the drums again to get them out. But the good news is it is better! You are in the right area.

BenPerfected , I had them turned at O'Reiles Auto parts.. They are pretty much worthless when it comes to anything that is not in there computer. I have had the shoes shaped on other brake jobs but they don't do it. It is a good idea though . I will check around to see about getting it done after the holiday weekend..
Tote-N-One, The finish looked good and smooth, I couldn't tell if there were any chatter marks. On the shoes I could see that they were contacting in the middle and not on the outer ends of the shoes. Exactly what BenPerfected was talking about.
I am going to sink it in the water this weekend and see what happens. Why not put some water and dirt in the test. Going to brake hard and hope it burns in. I will figure this thing out! At this point it is a matter of principle. At least I can drive it now. Before it was unbelievable.

Some brake linings are more aggressive than others. Some brake linings become more aggressive than others during use and / or abuse. You may want to try new lining. You may want to try new lining that is different from that used before.

Well Revd, I think you can rule out the master cylinder. I replaced mine, bled the sh*t out of them and it made no difference. Talking to Ameritrail the other day, they suggest to add brakes to the back axle. WTF! If thats the case why didn't they do that when they built the trailer. Structurally they are fairly nice but I really think they skimped in the brake dept.

I will be getting some new brake shoes next week and install them and see what happens. The old ones look decent with lots of material left ,but at this point I've replaced everything else but the shoes. I'll let you know how it goes.

Well my brakes are fixed!!:D As they should be as I just about replaced everything. I checked on new shoes and it was only $10 more for the complete brake assembly! (Backing plate,wheel cylinder, shoes, springs, everything) WTF. So I got the complete assembly. Installed everything, bled the brakes and preso!! Brakes worked perfect. Looking back onsome of the earlier posts ,I wish I had swiched over to a disc set up. At the time I figured I could fix the problem simply and already had money in both wheel cylinders.( Now I have 2 spares) and didn't think I would have to go this far to fix the problem.What I figure happened is the wheel cylinder stuck, got the brake and drum real hot and warped the drum and messed up the pads on one wheel. I am just happy it is all fixed and thank all of you for your help.

Turnerrd, Ameritrail's brake suplier is Quality trailer Products. You can buy direct form them at wholesale which is half what Ameritrail charges you. They have a branch in Angola, IN which can't be too far from you. There phone number is
1-877-730-3748. Also can check them out on the internet. If yours is chattering like mine was. I would turn the drums , buy the complete brake assembly's and that should fix your problems. Otherwise go the disc route.

Thanks Revd.

I put my new 10" brake assemblies on from Quality trailer and problem is fixed! They work great now, no clunking, locking up etc. Smooth as can be. Both brake assmblies where only like $80. The only thing I didn't get was galvanized back plate. Mine is just reqular powder coated steel. It should be just fine for fresh water dips anyways for a long time.
I'm still not exactly sure what was wrong with the old brakes. Everything appeared to be fine at first look. I'm just glad its fixed. Hopefully this thread will same someone else time and grief in the future.

One other thing I did was to lay under the trailer and tighten every U bolt nut and fastener I could find. Also took a really close look at the axles to make sure there were no cracks and just did a real good visual inspection of everything.

Glad to hear your brake problem is fixed!