Disc Brakes?

Magnetic Brakes heat up significantly hotter than other types, I've been told. Wouldn't it be better if the TM's had disc brakes? TM's need brakes that don't get so hot. Any opinions?

Originally Posted by Lanpherjd

Magnetic Brakes heat up significantly hotter than other types, I've been told. Wouldn't it be better if the TM's had disc brakes? TM's need brakes that don't get so hot. Any opinions?

I think I am following your question, which is do magnetic/electric DRUM brakes get hotter than other trailer brake systems ( which are hydraulic, hydraulic/electric, and air)?

We can leave air brakes out of this, as not being feasible for the vehicles with which we pull our campers with. You need to think the big trucks, which have air compressors on them to run the air brake system.

Brakes get hot when applied. The more you apply them, the more heat they will generate. When they are not applied, the air circulating around them, helps cool them off. DRUM brakes don't get as much airflow to help cool them off as do DISC brakes, so in a since DISC brakes are capable of cooling themselves off quicker if they can get the airflow.

Now to trailer brakes. Magnetic/electric brakes are drum brakes.

To have disc brakes on a trailer, you need to have a hydraulic system in place. However, even then, a vast majority of the hydraulic systems still use drum brakes. Many U-Haul trailers use hydraulic drum brakes.

Hydraulic brakes can then be broken down into 2 systems. A surge brake system and a electric over hydraulic system. U-Haul uses this surge brake system, because it requires no brake controller in the tow vehicle. It's almost a plug and play thing. A surge brake system has all the hydraulic system mounted on the trailer, and when you brake, inertia pushes an actuator rod which applies pressure to the brakes (like your pushing a brake pedal on your vehicle). My manager, who used to work on trailer brakes, personally hates a surge brake system. He said what they don't tell you, is that on light trailers (which Trailmanors are) with a surge brake system ,if you get on bumpy roads and it starts doing much bouncing/movement, the surge brakes will start intermittently grabbing just on the trailer each time it pushes against the tow vehicle....and will start jerking you all over the place.

An electric over hydraulic system, uses an electric brake controller, that when you apply your vehicle brakes, it then sends al electric signal back to the trailer's hydraulic system, making it apply the hydraulic brakes. On this system, it requires battery power on the trailer to the electro controller there that actuates the hydraulics, as well as all the hydraulic components.

A hydraulic brake system (whether disc or drum) on a trailer is initially more costly, more difficult to service for the average person, and not necessarily better. The main benefit of hydraulics brakes vs electric brakes is on boat trailers, that are being submerged underwater to launch/retrieve boats. Saltwater especially, will eat up magnetic drum brakes fairly quickly. They are making some magnetic brakes now with stainless steel components, etc just for this reason.

Personally, I don't think the added cost, weight, or serviciblity of a hydraulic brake system on a TrailManor is feasible.

If you have a good electric brake controller, set it properly EACH time you use it, and don't just stay on the brakes when up in the mountains......a magnetic DRUM brake system is just a good as the hydraulic one. You do need to manually adjust your trailer brakes from time to time. There are other forum post that will guide you on that.

We use magnetic brakes on our tire trailers that haul #12000 + without any problems.

I may get a difference of opinion on this, and welcome more comments on this great question.

[arniland]

I would have to concur with Bobby's comments. Over the past 6 years, I have put tens of thousands of road miles on my enclosed trailer with typical electro/mechanical drum trailer brakes. We haul an antique car around the eastern half of the U.S. I have no problem with hot brakes. However, I keep them properly adjusted and downshift the tow vehicle to hold speeds down on long, steep downgrades. At each stop I walk around and touch each wheel and brake drum. I have not found heat to be an issue.

A year ago I researched disk trailer brakes for a friend with a much larger enclosed trailer. The system I looked at (Dexter?) used an additional, electronically activated, hydraulic master cylinder mounted on the trailer to activate the trailer's disk brake calipers. It was expensive, heavy and complex. While it was a technically superior system (in theory), we could not justify all of the cost and effort. Weight was not a consideration.

In researching the Marathon tire issue I have read the postings of many members of this forum, but I don't remember any discussions of brake heat problems. Frenchy, for instance, has done 28,500 miles of travel with his TM (http://www.trailmanorowners.com/foru...ead.php?t=6870) and makes no mention of brake problems.

IMHO - If it ain't broke, don't fix it. Life will find enough things for each of us to worry about.

Arn

As a pure guess, I never have my foot on the brakes for more than 10 seconds, unless I am stopped at a signal. A second guess is that once I use the brakes and release them it will be at least one minute before I press on the brakes again. With this usage pattern I just don't see much risk of brakes overheating.

I down shift when appropriate. I driver slower when appropriate.

However, I don't normally drive in the Rockies either, only the Sierras. And I don't drive in the desert, but the central valley certainly gets hotter than 100 degrees.

From my limited experience, for brakes to get too hot there must either be a defect or non-optimal use of the brakes. I've only been towing for 3 years, but driving for 40.

We had the front brakes, disc, on a 1986 Ford Crown Victoria wagon get hot and ignite the plastic backing plate once. The cylinder was dragging and the brakes did not fully retract. There was always a small amount of rubbing that was not noticeable. This falls into the category of a defect.

Drum brakes have a feature that makes them beneficial over disks (besides cost). Drum brakes are often designed to be somewhat self exciting. When the cylinder or magnetic servo engages the shoes and they grab the drum, the assembly rotates and tends to grab more aggressively. Think of it like a door stop. Push harder on the door and it grabs harder. In this way the servo doesn't need to be as powerful as one on the more linear geometry of disk brakes.

Drums also have better static holding power which is why they are often used in for parking brakes too. Many vehicles actually have small drums hidden within the rear disk units because a suitable disk caliper with parking brake couldn't be designed. Those cars with rear calipers equipped with parking brakes often use a pedal for the ebrake instead of a handle due to the force required to activate them.

The draw back, as noted, is the poor heat dissipation on drums that causes outgasing of the brake lining and hence fade.

[Joesjunk]

While were on the subject of brakes... What is the life of the drum brakes on the TM? I have a 2000 TM and I doubt that the brakes have ever been looked at?

Thanks,

I had my brakes inspected and the bearing hand packed a month ago. After three seasons my mechanic says I should put brakes on next year.

This is for 21 trips and 7500 miles.

hth

fwiw, my mechanic says that it is cheaper to replace the brakes on the trailer than on the truck. Therefore, it becomes tempting in some circumstances to manually engage the TM brakes and not use the truck brakes. I'm not sure I believe that, but it is what he said.

[Mr. Adventure]

Originally Posted by PopBeavers

I had my brakes inspected and the bearing hand packed a month ago. After three seasons my mechanic says I should put brakes on next year.

This is for 21 trips and 7500 miles.

hth

fwiw, my mechanic says that it is cheaper to replace the brakes on the trailer than on the truck. Therefore, it becomes tempting in some circumstances to manually engage the TM brakes and not use the truck brakes. I'm not sure I believe that, but it is what he said.

That sounds way too soon for brakes on the trailer (next year would put you at roughly 10,000 miles), but maybe the mechanic was overstating his process of preparing you to spend money at next year's visit, as those guys occasionally do. If you really were getting just 10,000 miles between brake jobs on the trailer, it's hard to imagine that being economical relative to the service you get from the brakes on your tow vehicle. But I guess it still comes down to just "how much" and "how often".

Originally Posted by Mr. Adventure

That sounds way too soon for brakes on the trailer (next year would put you at roughly 10,000 miles), but maybe the mechanic was overstating his process of preparing you to spend money at next year's visit, as those guys occasionally do. If you really were getting just 10,000 miles between brake jobs on the trailer, it's hard to imagine that being economical relative to the service you get from the brakes on your tow vehicle. But I guess it still comes down to just "how much" and "how often".

My dad used to own a "gas station" many years ago. I know full well what those guys are capable of.

My mechanic has been working on my vehicles since 1986. I have great confidence that I am not getting ripped off by him. However, he also is not the cheapest guy in town.

What he actually said was that the pads were at the half way point. Also, I only camp in the Sierras, between 5000 and 8000 feet. A lot of my miles are in the mountains. Therefore, I would not be surprised to see that my brakes wear faster than normal. I use the transmission when I can, but driving down the mountains in heavy traffic results in using the brakes a lot.

[Joesjunk]

Looks like it is time to pull the wheel and check the brakes on my 2000 TM. Planning a cross country next year of about 10,000 miles.