Surge brakes for <3000# single-axle rig; do I want drum or disc?

[ajgraz]

17' CC on a galvanized single axle LoadRite trailer (believe to be model year 2000), total loaded weight of entire rig (hull, motor, trailer, gas, batteries, gear, etc.) is ~2800#

Recently replaced the springs because the originals were shot; went ahead and upgraded to a new Dexter EZ Lube 3500# axle while I was at it, since LoadRite apparently believes that 1" inner bearings makes for a 2700# axle, while the entire rest of the world calls that a 2000# axle. (Also, inner seal surface on spindles worn and no longer sealing grease.)

New axle has standard brake mounting flanges.

Never had a trailer with brakes before, but I'm thinking about adding surge brakes for an added safety factor (I tow with an old Dodge Dakota). In general, I know that disc brakes are better than drum brakes (at least in automotive applications)...but according to Champion Trailers, trailer under 3000# actually does better with drums than discs, because the lower weight can't apply enough surge pressure for discs:

https://www.championtrailers.com/dis...s-drum-brakes/

So first question: does anybody buy that argument?

(EDIT: use is 100% saltwater, if that impacts the decision)

 

[Scott Danforth]

I used drum brakes for years in salt water. i am using disc now, however my boat/trailer combo is about 5200#

part of my ritual was to rinse the brake drums out when I washed the boat.

drum brakes are self-energizing when applied where disc are not. drum brakes are also self-backing, where disc requires a blocking solenoid. so the load under 3000# will stop easier with drum vs disc

either way, go with copper-nickel brake line (anything else will be eaten by rust)

with proper maintenance I would go either way.

 

[ajgraz]

The ability to get free-backing drums definitely adds to their appeal...much simpler!

Next Q was going to be about brake lines...what about rubber lines the whole way?

 

[Scott Danforth]

rubber lines flex and reduce your pressure the longer they are. its an issue that some can live with. i personally keep rubber as short as possible

 

[dingbat]

Had free-backing on my first trailer. Never again. Couldn't pay me....

Saltwater use........it's not if they seize, it's when and where.......removing a glowing brake drum to get home in the middle of the night on the side of Rt. 95 (second brake failure that season) made the decision to go to disc pretty easy.

I've had Stainless, terne and now rubber brakes lines on my trailers. The rubber brakes lines where easy to install and maintain but the braking power is noticeably reduced from the hard lines they replaced.

When it comes time to replace the rubber lines, I'll spend the money and going back to stainless.

 

[ajgraz]

Tell me more about the problem(s) specific to free-backing drums?

As for siezing...maybe a dumb question, but if the actuator had a manual lock-out, would that "unsieze" them enough to get home?

 

[Scott Danforth]

what siezes on drum brakes is the wheel cylinder bores get corrosion in them. if the brakes are not adjusted often, as the shoes wear, the pistons in the wheel cylinders move further out than normal and get hung up in the corrosion and the actuator is stuck "on". the galvanized backing plate assemblies with aluminum wheel cylinders with the anodized bores significantly reduces the chance of this however does not eliminate it. adjusting the brake shoes often and inspecting the brakes annually is a must.

if they stick, simply back up, stop, and adjust the shoe adjuster

Disc brakes have their issues too. I have replaced my disc brake calipers (kodiak stainless) due to caliper sticking and the pads cooking the seals and had the reverse solenoid fail once.

 

[dingbat]

As for siezing...maybe a dumb question, but if the actuator had a manual lock-out, would that "unsieze" them enough to get home?

unrelated to the coupler.

As Scott noted below, usually a stuck / seized wheel cylinder. Nothing you can do except remove the hub and take the pads off to get home.

Disc can fail as well but have proven much more reliable for me. Had a sticky caliper (dry slidef pin) home from the beach last year. No drum to remove to inspect. Installing the coupler lockout pin got me home.

To be honest, I’m not one to spends hours coddling the boat and trailer after each use.
I use it too often for that. Somtimes 5-6 days a week

The rods and boat get a good rinse. The trailer gets a half hearted effort at best if I’m leaving again in the morning.

 

[Lou C]

This is a something that has been discussed ad infinitum, most will agree that discs are less trouble, but they can still seize up, from salt deposits getting to the piston in the caliper, which is the same problem that drum brakes have, but it takes longer for that to happen with discs. I have a couple of solutions to the drum brake seizing issue:

1) with conventional aluminum wheel cylinders, they can be made more water proof by:
starting with a new wheel cylinder, remove the dust boot, coat the upper edge of the piston and fill the inside of the boot with OMC triple guard grease.
then, seal the boot to the cylinder with high temp rtv and also seal the piston rod where it passes through the hole in the boot. I have found that by water proofing them this way, they will go about 2x as long before seizing, maybe more

2) UPF makes a new style cylinder that does not use a boot, rather it has an external o-ring to make the seal, not allowing water a place to get in and collect. They also sell zinc or galvax coated drums that last a lot longer. A few trailer places do sell them, google 'bootless drum brake wheel cylinder'

3) I also will set my drum brake adjustment a bit on the loose side, so there is no drag at all. Why, well that way the drum shoes do not get stuck to the drums when the trailer is parked.

 

[Lou C]

Bootless wheel cyl and zinc plated drum....

 

[ajgraz]

...2) UPF makes a new style cylinder that does not use a boot, rather it has an external o-ring to make the seal, not allowing water a place to get in and collect. They also sell zinc or galvax coated drums that last a lot longer. A few trailer places do sell them, google 'bootless drum brake wheel cylinder'...

Lou, thanks for the info on how to better "seize-proof" a standard cylinder.

Call me dense, but I'm not finding much when I google 'bootless drum brake wheel cylinder' I find a few various forum posts about the subject (though oddly, not this thread or any iboats threads), a few cylinders in the "shopping" section (that don't really say they are "bootless"), and not much else.

Any chance someone could post a link to a set of galvanized, free-backing, 10" drum brakes that are confirmed to have these bootless cylinders already in place?

 

[ajgraz]

Had free-backing on my first trailer. Never again. Couldn't pay me...

Also, still awaiting an answer to what problem(s) are specific to free-backing brakes.

 

[dingbat]

Also, still awaiting an answer to what problem(s) are specific to free-backing brakes.

Nothing special about free-backing brakes. Just a different pad configuration from "drum brakes". Everyone of the problems / pit falls of drum brakes noted above applies to free-backing as well.

I'm not the local brake salesman so I'm not here to sell you on one configuration over the other. Just relaying my personal experiences with drum style brakes in regular saltwater use over the past 30+ years.

As noted above, I don't baby my equipment be it the boat, tractors, or the numerous pieces of farm equipment I maintain. If I can reduce my work load by something as simple as not needing to pull a brake hub to inspect the brakes I'll do it.

List of "free-backing" issues I've had over the years:

1. Adjusters rusted solid
2. Stuck wheel cylinders
3. Broken return springs
4. Pads stuck to drums after sitting for any length of time (backing up typically broken loose)
5. Excessive pitting on the inside of the drums from lack of proper drainage
6. Excessive brake shoe wear from #5, decreased braking performance.
7. Need to remove drums to inspect inner workings

List of "disc brake" issues I've had over the years:

1. Sticking caliper sliders (requires silicon grease lubrication... apparently more often than every 5 seasons...lol)
2. Melted a Tie-Down aluminum caliper from a stuck piston (prompted change to Kodiak with SS piston and caliper bores)
3. Excess pad wear from rusting discs (Ceramic brake pads increase life x 3)

 

[Scott Danforth]

all drum brakes are free-backing. the nature of drum brakes is they self-energize in one direction, and they free-back in the other.

it is this vary reason that power brakes (vacuum assisted or hydraulic assisted) did not emerge in the automotive world until the disc brake was mainstream in the early 70's.

 

[dingbat]

all drum brakes are free-backing. the nature of drum brakes is they self-energize in one direction, and they free-back in the other.

Uni-servo drum brakes on a surge actuator will have noticeably more resistance (20% braking power by spec) in reverse than free-backing brakes.

That leaves the question, does your vehicle have a problem pushing against the 20% resistance?


https://www.demco-products.com/assets/users/documents/BC20002.pdf

 

[Lou C]

Sorry to disagree Scott but power drum duo servo brakes were everywhere in the old days when I started driving, way before disc brakes became standard at least on the front. My uncle had them on a 1956 Olds Super 88 and on a 1964 Olds Dynamic 88, they would stop at the touch of your toe!
Un-assisted (manual) drum brakes on cheap bottom trim line cars took huge pedal effort to stop. What makes trailer brakes free backing is the uni-servo piston cylinder and the linkage that causes one shoe to 'fall back' when backing up. Duo-servo drums do not have this design and are not free backing. In fact, automotive drums were Self Adjusting in reverse, so they had to work, for the self adjusters to work! You backed up and hit the brakes hard, that would cause the shoes to shift and actuate the self adjuster to tighten them.

As far as boat trailer drum brakes issues like I said, the wheel cyl issue is solv-able (for the bootless cyls, I cannot post a link here, but the place that sells them....is on the west coast.....UPF brand......same with the zinc plated drums). Take a REAL close look at the pic of the cyl I posted.....

other problems and solutions:

Drum corrosion--go with zinc or galvax plated drums, mine are 14 years old
Drum shoes sticking to drum, I covered that, adjust them so the shoes do NOT drag, at all
Adjuster corroding, all you need to do is pack the threads with OMC triple guard grease with the adjuster all the way backed out, they will not seize then.

I looked at conventional drum brakes and analyzed the failure patterns and came with a way to deal with each one. Works for me. Keep in mind, salt water does get past the dust boot on the disc brake caliper too. I'd advise if you do go with discs, to remove the calipers at the end of each season, clean all the salt crystals out and coat those boots with disc brake caliper grease. Of course grease the slide pins as well. And if you don't use stainless rotors, in salt, they seem to rust as bad or worse than drums, with big chunks of cast iron falling off.

 

[4now04]

The drum brakes I had on the last trailer would engage and make backing up hill difficult, maybe not as much as disk brakes but definitely noticeable. The disk brakes are a lot easier to rinse out because they are a much more open design. All brakes need care. Drum brakes may have automatic adjusters. These do not always work well. They tend to rust and not work. With any brake system, there is a possibility that one brake may not work as well as the other. In these situations un-even brake effectiveness can cause the the trailer to pull to one side. This can become an "interesting or exciting" ride when stopping. A coating of grease can help reduce corrosion, but that grease can almost eliminate brake effectiveness. This can happen when over-greasing wheel bearings pushes the grease past the inboard grease seal and coats the brake shoes. Whether you have disks or drums, having enough grease on hot areas of the brake system can cause a little smoke and the aroma of burned grease. That is an interesting feeling when you look in the rear view mirror and see a little smoke coming off a wheel . ;-)