Disc Brake Conversion

[JMetzger]

I am wondering how many of you have converted your RV drum brakes to disc brakes & how do you like them & where & how much did it cost for the conversion?





Jack

 

[Mark31]

Jack, I believe that a poster in one of the ongoing brake controller threads said he was considering replacing his shoes with discs, but the Maxbrake (or maybe Brakesmart) made such a difference he was having second thoughts. How would the cost of a Maxbrake and exhaust brake compare with the cost of the disc conversion? How would the stopping performance compare? Mark

 

[HBarlow]

I am not at all impressed with trailer disc brakes. I pulled several of them when I was transporting and did not like them. The discs absolutely can provide great stopping power, of that there is no doubt. You can grab the override button on your brake controller at 60 mph and look in your rear view mirrows to see the tire smoke.

But, unless the disc brake systems have improved significantly in the last three years disc brakes produce an inherent delay between the time the driver pushes the tow vehicle foot brake or the override on the brake controller and the time the trailer brakes actually begin braking. I found that delay very scary when pulling a heavy trailer on an LA freeway or on the interstate in a big city with heavy traffic. The delay was something like two or three seconds before trailer braking occured. A 24,000 lbs. truck and trailer can travel a very long distance at 60 mph in rush hour traffic before braking is applied. I read an article several years ago in Trailer Life magazine that discussed that delay back when hydraulic disc brakes for RV trailers were first introduced. When I towed trailers with that option I understood what they were talking about.

The reason the delay is present is the time it takes for an electric hydraulic pump to create hydraulic pressure. The trailer braking system does not and can not operate like truck hydraulic brakes because it is not safe to physically connect the hydraulic lines of the tow vehicle to the hydaulic brake lines of the trailer. No hydraulic braking pressure is present until an electric signal reaches the electric hydraulic pump and the pump spins up and generates pressure to the calipers. This takes time.

Instead of ordering the hydraulic disc brake option on my HitchHiker fiver when I bought it in '07, I paid a few hundred dollars for the larger self-adjusting Dexter brakes. They are something like 2 1/4" by 13" instead of 2" by 12".

Combined with a BrakeSmart brake controller, my HH has outstanding brakes.

 

[NIsaacs]

Electric drum brakes have been around for years and they work good.



However if you really want hydraulic disks, there is a good system that is common for medium duty applications. They come in air over hydraulic or vacuum over hydraulic. It will require a vacuum pump, hand valve simular to an air hand valve in a big truck and two lines (again like air lines on a big truck) for constant vacuum for the storage tank and applied vacuum for the vacuum master cylinder. They are progressive and work awesome, however spendy if you are starting from scratch.



Nick

 

[JMetzger]

Harvey, I was wondering about a delay as they never mention it but I felt that there had to be one. Thanks for the info.

 

[rknichols]

Try the MaxBrake before you spend the money on disc's.

I've been thru several brake controllers and the Max
Brake is superior to anything I've used.

I thought I had brake problems on the 5th but that was not the case.

I run on approx setting 30 (out of 99) and I never feel the trailer brakes. No delay, just smooth stopping.

I think if I used the slide switch that I could that I could slide the 5th wheels tires.

Highly recommended. Same technology that was used in the 70's before anti lock brakes.

 

[JMetzger]

rknichols & Harvey, as soon as I can scrape a couple dollars together I am going to get a Max Brake. It is a heck of a lot cheaper then disc brakes. My 32ft Holiday Rambler has really never had the best brakes from the factory but they will stop it but hard to lock up brakes. I guess that was Holiday's answer to anti lock brakes.

 

[AfterBurner]

My '08 Bloomer has disc brakes and I have never noticed a delay. All my other trailers before had drums and I can't say enough good about these discs. I have done several panic stops in heavy traffic and never felt the trailer was pushy at any point during brake pedal application. Of course during the panic stops I had other things on my mind, like where I can go if I can't get shut down, not particularly paying attention to the feel of the trailer, but I am pretty sure I would have noticed a delay in trailer brake application, especially as heavy as it is (usually runs 13K-17K).



The biggest point that I've felt a difference is on long steep grades, like the 6%-7% passes in CO. Brakes didn't fade as fast as drums and recovered sooner.

 

[HBarlow]

Jack,

I think you'll be pleasantly surprised with how much better your Holiday Rambler's brakes will be with a new MaxBrake activating them. As Nick Isaacs wrote above, trailer electric brakes have been around for a very long time and work very well when the magnets are good, the shoes are not worn out, and are properly adjusted. The secret is a good brake controller.

 

[NIsaacs]

Years ago a good friend of mine borrowed my tandem axle dually trailer to haul a load of wood pellets. He used his 1990 W250 with the Kelderman Air Ride system. He had to make a panic stop just a short distance from the Pellet Plant and forgot to turn down his brake controller. His normal trailer is a two axle car hauler with one axle brakes. When he hit the brakes (12 1/4 x 4"") they locked up, the weight transfer on the goose neck slammed his rear air bags flat, unloaded the front's and his rear bumper almost hit the ground. It ruined his pretty chrome metal mud flaps. The story he told was funny:-laf



Nick

 

[JMetzger]

Harvey, Like I said in a previous post I really liked my old Kelsey Hayes controller as it was tied into the hydraulics on my 76 Plymouth Van. Never had any problems, set it once & forgot about it. Harvey, as long as you have been around I bet you used one in your time. I have had solid state controllers since then because everyone said it was a no no to tie into the hydraulics because of the positioning valve on the dual master cylinder & I have never really been happy with any of my trailer brakes as it always seemed that you were adjusting the gain for slow to fast driving. Thanks. I hope to get a Max Brake soon.

 

[HBarlow]

Jack,

Yes, I confess to using an old K-H controller back when they were "the brake controller. " I bought my first travel trailer, a 23' Fleetwood Prowler in fall of 1972 and pulled it with a '70 Chevy C-2500 3/4 ton pickup.

For the TDR members who are still driving Dodge Rams with front disc brakes and rear drums the ordinary old Kelsey-Hayes hydraulic brake controllers work great. I gave one to an friend with an early 2001 Ram 3500 recently. He is using it to pull a large Carriage fifth wheel and tow a small trailer behind it with a VW dune buggy on the trailer. On my advice he put his Tekonsha Voyager controller which provided essentially zero braking in the garbage can.