How to loose a caliper on your trailer disk brake system..

Avidmagnum12

Avidmagnum12

Member
Leaving Grand Portage Minnesota after over 40 days at Isle Royal NP we had a trailer failure. Our tire pressure monitor started to show abnormal high temperature on one wheel. After stopping I saw that one of the caliper pins completely backed out and allowed the caliper to rub on the wheel. The caliper was ground down and only one brake shoe was still present. I tried to find a shop to fix it but no parts so no joy. I eventually was at a place where I could order parts and everything is back together after 6 days.

I have no one else to blame but myself as I do my own wheel bearing work. Colby Smith lost a caliper on a trailer he had and felt that this could have been the cause.

Here’s what I plan to do in the future.
1) inspect the pins every 1,000 miles.
2) use blue lock tight on the pins.
3) I will be carrying and extra caliper, brake pads, pin and fluid along with the other spares in the truck.

If you have disk brakes and tow longer distance, it mite not hurt to inspect.
 
Kodiak slide pins come with a blue thread sealer already on their threads. My brakes are a different brand and did not come with sealer. I watched one YouTube video where anti-seize was used on a salt water trailer. The brake shoes on that trailer were delaminating in less than a year. I guess that individual situations can call for different products.
 
I use silver or gold anti-seize on items like lug nuts, but it is the exact opposite of thread sealer. A little goes a long way.

We primarily boat in saltwater, so the anti-seize helps.
 
I use anti-seize compound on most brake and wheel bolts. Not sure if that is wise or not, but sure makes getting them off easier when the need arises. But I also try to check everything now and then. With my lost caliper, it was on the old Karavan trailer that came with my boat. (The new Loadrite is a much nicer trailer!) In that incident, it appeared the pin holding the caliper to it's frame broke off. I'm pretty sure that was a new unit put on by the earlier owner's mechanic recent to my purchasing the boat. This happened somewhere in the Rockies and when the caliper fell off, it took the brake line with it. Which resulted in the loss of brakes on both trailer axles. And like Tom, except I was in a little more civilization, no parts or shops could be found that would be able to work on it anytime soon. Needless to say, it was a very cautious trip with a lot of room left for stopping, the rest of the way home. I know Tom, and don't think it's anything he can blame himself for. Crap happens sometimes, and I think this was just one of those moments.
Interesting he first realized the problem with his tire monitors. Even with all my trailering, I still have not chosen to install tire monitors on my trailer. Not sure if this will convince me to or not... :| Colby
 
Use of Loctite 262 is specified by Tie Down Engineering for the caliper pin. It is a part subject to a lot of vibration while brakes are being applied.
 
Guess I should double check the pins on my new trailer. I haven't done any work on it regarding the brakes other than to remove the bolts that hold the caliper frame to the trailer, so able to remove the hub and bearings. Thanks for the info. Colby
 
I recently rebuilt the brakes, and made sure all pins had the blue loctite. Also have one set of brand new calipers not installed "just in case", along side extra seals, and bearings.
 
Looks like these pins are a problem. After launching yesterday at Rio Vista, after a 2060 mile drive from home, I noticed my trailer brakes making a lot more noise than normal. Inspecting them I found that both right trailer brakes had broken calipers. On one of the calipers, both pins had broken off. The other caliper one pin was broke off, while the other pin was missing. (I suspect the missing pin may have vibrated out...) The calipers were rubbing/grinding against the inside of the wheel rim, and that is the only thing keeping them from falling off and taking out the entire brake system! These were the original calipers on my new Loadmaster trailer, with around 24000 miles on it. I forget the manufacturer of the calipers, but they were not Dexter, and I suspect of cheaper quality. I did inspect the left side calipers closely, and they all look ok. When you look at the mechanics of these calipers, it is those two pins on each caliper that is taking the brunt of the braking force, as the bracket holding the brake pads is torqued in the direction of wheel rotation when you brake. The calipers cost $136. (I have found them cheaper, but then with shipping, back in the $140 range.) I did have a new spare Dexter caliper that I purchased and kept in my truck just for such events. I have two coming in to the local Napa today, one to replace the other broken caliper, and then another new spare. I do like the EOH brakes. But three new calipers cost just over $400. A new EOH actuator would cost around $800 if I ever need to replace that. For the cost of four new calipers, I could easily revert my system to entirely electric ($520) which would require new hubs and the electric brake backing plates. If I continue to have problems with calipers, I may just go back to all electric! Colby
 
I actually like drums just fine.....lol....As a side note, and everyone probably already knows this, the way to get loctite to loosen up is to apply heat - plenty of that in a brake system. In my experience, the red is better at staying put and does come apart with a torch or even a heat gun, usually....Obviously, use at your own accord as it is supposed to be "permanent".
 
Our tire pressure monitor system shows temperature. If your caliper is rubbing on the wheel you’ll know it! I’ll be sure to check my pins more often.
I don’t know anyone that tows more than you do. Keep us advised on your “Education!” LOL
 
I too will be checking my caliper pins, looks like a failure waiting to happen.

There is one thing I've pondered since owning an EOH system. The electronic controller mounted on the tow vehicle's dash area might be a contributor. My Tekonsha has 3 boost levels to send a steep pressure gradient to the electric master cylinder when first applying the brakes. After the first few (100's?) of milliseconds it reverts to the set braking pressure curve that was determined to match the rig's braking force required. That initial boost application could be shocking the calipers excessively and over 100's of brake applications might be fatiguing the caliper pins. So the question might be, are the pins breaking or backing out on just the EOH systems or surge braking systems as well?
 
Well, I'm still having a problem with the brake caliper slide pins. And it appears to start with the bushings! While very minor, after arriving at Marina Del Rey, I noticed that the bushings around the trailer caliper slider pins, on the right side, on the bottom, had all disappeared. I was able to temporarily fix this by using some red silicone and filling in around the pins. (Thanks for the silicone, Jim!) Sometime this week I will be pulling the calipers, cleaning out the silicone and replacing the bushings. But my question is, why is this happening! If you remember, I had both right side calipers come off, only being held by the tire rims, on that same side earlier this year when I drove out to Rio Vista for the Delta Cruise. That was because 3 of the 4 pins had broken off, with 1 pin completely gone. The bushings were all gone in that case as well. I suspect that the bushings came out, as this time, and allowed the calipers to break off the pins. At least this time I caught it before the pins were broken off. These were the brand new "dexter" calipers. The bushings were tight in the opening, as they should be. I'm wondering if it's possible the water when launching is dissolving the pin grease, creating friction allowing the pin to slowly push the bushing out? But it's only happening on the right side! Colby
 
Not sure what is happening. However back a few years ago I had defective calipers : Guess where there they were made!~!

A bad casting could allow the pins to break and the holes where the bushings are, enlarge.

Another item to check is the pressure on both aides. It is possible that there is restriction of the fluid flow on one side. Thus stressing the other side's brake system
 
Hi Bob,
I don't think the pressure is asymmetrical, as the trailer feels to be tracking straight when I apply the brakes. I didn't notice rounded out holes on the two old calipers that I rebuilt. (The ones that had the pins break earlier.) Not sure where Dexter calipers are built, but I think regardless, these appeared to be heavy duty and well made.

Alain, I'll look and see what number is stamped on the calipers when I work on them later this week or next. Colby
 
alainP":2jmkgood said:
Colby, is the number stamped on your calipers #46304?
Click to expand...

Hi Alain,
The number on my calipers is 89-135. They are basically referred to as DB-35 calipers.

I did email Dexter and I'll share what and if I get a response. I did check the wheel bearings on that side of the trailer and while I think they were within limits, I did tighten the bearing nut up one space on the cotter key. (Pretty much finger tight without needing a wrench to go any tighter.) There is no freeplay now in one of the axles and very little in the other. I'll see what happens over the next couple of trips, but nothing that will add up to more than a thousand miles the rest of this year. Colby
 
We do have diferent calipers, that would explain why we have different problems.
On this last trip to Lake superior I somehow lost one inner brake pad, the aluminum piston melted itself away when pushed all the way to the steel rotor and brake fuid was squirting out.
Fortunatly i had a spare caliper w/pads and a quart of brake fluid in the truck. I I got to know some really nice people in Dumas Tx,
 
alainP":2u6y3jf0 said:
We do have diferent calipers, that would explain why we have different problems.
On this last trip to Lake superior I somehow lost one inner brake pad, the aluminum piston melted itself away when pushed all the way to the steel rotor and brake fuid was squirting out.
Fortunatly i had a spare caliper w/pads and a quart of brake fluid in the truck. I I got to know some really nice people in Dumas Tx,
Click to expand...

Would be interesting to know how that happened... While the electric over hydraulic disc are nice brakes, the expense is already proving to far exceed just plain old electric brakes. Not to mention the time involved to repair them. IOW, they are a real PITA at times! I never had this much issue with all electric. The biggest disadvantage with all electric is you have to pull the wheel and drum to inspect the shoes! :( Colby
 
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