Brake assistance

[CDenton]

Need help. Have a 2010 dodge 3500 with built in tow package and just bought a brand new 2011 DRV mobile suite 36 foot fifth wheel with an electric over hydraulic brake system. Problem is that even with the brake control on the pick up turned up to the max there is a 3-4 second delay before the trailer brakes apply. Is the standard? Is there an adjustment on the DRV or do I need to change the pick up brake control. We called he trailer dealer but they are not much help. please help.

 

[B.G. Smith]

I have an 04 Newmar with the electric operated hydraulic brakes. There is definitely a delay, it takes the unit a short period of time to pump up the trailer brakes. I am using a plain jane time ramp controller. Sure have to be careful or you will lock em up and flat spot some tires. I thiught maybe they had comme up with some improvements to shorten the time delay, might have to live with it. Great brakes otherwise. bg

 

[HBarlow]

The time delay issue is always ignored in internet discussions by those who own large fifthwheels with expensive optional hydraulic disc brakes. BG Smith is the first and only honest owner I have ever run across who acknowledges that fact on a website.

It is always present in every trailer hydraulic braking system regardless of manufacturer, design, components, or wishful thinking by the buyer although some may respond faster than others. The reason is the braking system has no line pressure under static conditions. When the driver calls for braking with his right foot on the pedal the hydraulic pump at the trailer is activated and begins pumping up pressure. That requires an amount of time. It is simply not as fast as manually pushing a plunger in the master cylinder with your right foot.

Hydraulic trailer brakes are the absolute best braking systems available without a doubt. They are capable of locking all four or all six wheels instantly --- after a delay. It is that delay that I could not tolerate. Towing at 60 mph on a Los Angeles or Chicago or Atlanta freeway or on I-15 through Las Vegas your truck and trailer will travel a long distance between the time you step on the brake pedal and the time you can lock the trailer brakes. That is the reason I declined that feature when I ordered my HitchHiker back in early '07. I ordered the Dexter HD brakes which are, IIRC, 2 1/4" by 13" drums. They are very powerful drum brakes that apply instantly although they are not as powerful as discs.

I pulled a couple of heavy Alfa fifthwheels with hydraulic discs when I was transporting. I didn't like them at all. Towing in heavy traffic I was nervous enough to hold my right index finger on the big red manual override button on my BrakeSmart controller when traffic closed in. I could punch that button and look back in my mirrors and see smoke billowing off each side of the Alfa but I couldn't live with the delay.

Now, after making my hydraulic disc brake speech, back to the OP's question.

Your largest problem may be the truck brake controller not the trailer's hydraulic brake system inherent delay. With a good brake controller the effect of the hydraulic brake delay can be minimized.

I believe the OEM optional brake controller in new Rams is an inertia sensing controller. It is worthless if I am correct. The reason I say that is in order for the OEM brake controller to apply trailer brakes it must first sense negative acceleration. The truck has to create negative acceleration or deceleration by itself with a heavy trailer behind it before the brake controller can sense braking and apply trailer brakes. Bad design. It is the same lousy design used by Tekonsha in their sorry Prodigys and the forerunner which name I have forgotten as well as other inertia sensing trailer brake controllers.

The fix is to install an aftermarket MaxBrake and have the dealership disable the useless factory controller. See Don Dyer (Domehead)'s and my article in the recent issue of TDR magazine for instructions.

 

[Blu-meanie]

Maybe some engineer will install an accumulator in the mix... . end of problem.

 

[GCroyle]

CDenton,



Please consider inspecting your brake calipers:



1. Are they single piston or do you have pistons on both sides of the caliper?

2. If dual piston, where does the brake hose attach at the inboard piston, and WHERE physically does the transfer tube connect from inboard to outboard?

3. If dual piston, please describe the connection of the brake hose to the caliper casting? Banjo bolt, threaded flare on the end of the hose etc.

4. If dual piston, is there a bleed screw on inboard AND outboard?

5. Just curious, what brand axle and brakes?



A picture might answer all of these questions



My TT has electric actuator also.

 

[tarnett]

Harvey,
I have to comment on the disk brake delay since that has not been my experience. My 5th wheel is using a Tow Brake HD3000 with disc brakes & dual axles and on their web site (FAQ section) they have the following:

How fast can you get to full pressure?

The HD series can achieve full 1600lbs of pressure (for disc) in as little as 8/10s of second. That timing is to activate 6 disc calipers or 3 axles of brakes. For tandem axle disc systems the time to pressure is less than half a second. To reach full pressure on a drum brake system (1000 lbs) the time is a little over 1/2 second.

That . 5 second delay surprised me in that I have not noticed it when towing. But then perhaps 1600 lbs pressure is considerably more than what the majority of my braking involves. While I agree that any delay can be serious that does seem to be minimal. Do you agree? There must also be some delay with drums using other controllers as well, yes/no?
Thanks,
Tom

 

[HBarlow]

Tom,

My knowledge of the subject of electric over hydraulic disc brake systems does not include actually owning one. Several years ago, when the systems were first offered, Trailer Life ran a good technical article based on a towing test with the system. The article explained and discussed the delay in detail.

When I was transporting I pulled two or three brand new large and heavy Alfa Gold fifthwheels from the factory in Corona to dealers, one in Austin, TX. I found the inherent delay unacceptable in LA freeway traffic. I was using the best brake controller money can buy, a BrakeSmart. There were no delays or any problems whatsoever with that brake controller and ordinary electric trailer brakes.

Even when I held my finger directly over the manual brake override button which probably took a microsecond to press full travel, the disc brake system exhibited a natural delay.

BG Smith posted above that he owns a Newmar which is a large and heavy fiver. He says his definitely has a delay.

The specs you quoted were posted on the manufacturer or vendor's website. Are the specs accurate or were they slanted in favor of their product? I don't know.

That's all I have to say on the subject.

 

[tarnett]

Harvey,
I would hope Tow Brake's Welcome to Towbrake.com information is accurate but I can only say for certain what has been my experience with their unit. So far so good!
Tom

 

[HBarlow]

Tom,

Towbrake claims their system uses the brake controller's output voltage to actually push the piston in a hydraulic master cylinder, not to activate a hydraulic pump.

That is an entirely different system I had never heard of. I interpret that to mean their system uses an actuator, like an electric solenoid I suppose, to duplicate the driver's foot pressing the piston in the master cylinder.

I can see how that eliminates the time delay. Must be a fairly recent development for electric over hydraulic trailer brake systems. It's new to me. That system was not offered in early '07 when I ordered my HitchHIker. I think NuWa was using a Dexter system. Don't know what they use now or if Dexter now offers a similar system. Towbrake may have a patent on it.

From their website: "How does your unit operate?

The HD interprets a signal from your cab controller and causes an actuator to push in on a hydraulic master cylinder. We have used this unit with several different brands and types of controllers and we have not found one that our unit has not responded to. "

 

[B.G. Smith]

Harvey,

I would hope Tow Brake's Welcome to Towbrake.com information is accurate but I can only say for certain what has been my experience with their unit. So far so good!

Tom

I would like to know more about this setup, however their statemnt under "What is the advantage of 2 hydraulic ports" about the rear axle having less load under stopping conditions is not correct. When brakes are applied the torque of the front axle pushes the equalize link up and the rear axle torque pushes it down thus lifting the front axle. That is why on tandem axle trailers, if they only install brakes on one axle it is the rear. bg

 

[Top Gun]

The time delay issue is always ignored in internet discussions by those who own large fifthwheels with expensive optional hydraulic disc brakes. BG Smith is the first and only honest owner I have ever run across who acknowledges that fact on a website.



It is always present in every trailer hydraulic braking system regardless of manufacturer, design, components, or wishful thinking by the buyer although some may respond faster than others. The reason is the braking system has no line pressure under static conditions. When the driver calls for braking with his right foot on the pedal the hydraulic pump at the trailer is activated and begins pumping up pressure. That requires an amount of time. It is simply not as fast as manually pushing a plunger in the master cylinder with your right foot.



Hydraulic trailer brakes are the absolute best braking systems available without a doubt. They are capable of locking all four or all six wheels instantly --- after a delay. It is that delay that I could not tolerate. Towing at 60 mph on a Los Angeles or Chicago or Atlanta freeway or on I-15 through Las Vegas your truck and trailer will travel a long distance between the time you step on the brake pedal and the time you can lock the trailer brakes. That is the reason I declined that feature when I ordered my HitchHiker back in early '07. I ordered the Dexter HD brakes which are, IIRC, 2 1/4" by 13" drums. They are very powerful drum brakes that apply instantly although they are not as powerful as discs.



I pulled a couple of heavy Alfa fifthwheels with hydraulic discs when I was transporting. I didn't like them at all. Towing in heavy traffic I was nervous enough to hold my right index finger on the big red manual override button on my BrakeSmart controller when traffic closed in. I could punch that button and look back in my mirrors and see smoke billowing off each side of the Alfa but I couldn't live with the delay.



Now, after making my hydraulic disc brake speech, back to the OP's question.



Your largest problem may be the truck brake controller not the trailer's hydraulic brake system inherent delay. With a good brake controller the effect of the hydraulic brake delay can be minimized.



I believe the OEM optional brake controller in new Rams is an inertia sensing controller. It is worthless if I am correct. The reason I say that is in order for the OEM brake controller to apply trailer brakes it must first sense negative acceleration. The truck has to create negative acceleration or deceleration by itself with a heavy trailer behind it before the brake controller can sense braking and apply trailer brakes. Bad design. It is the same lousy design used by Tekonsha in their sorry Prodigys and the forerunner which name I have forgotten as well as other inertia sensing trailer brake controllers.



The fix is to install an aftermarket MaxBrake and have the dealership disable the useless factory controller. See Don Dyer (Domehead)'s and my article in the recent issue of TDR magazine for instructions.

Harvey,



Just looking for some clarity on something :



would you say then that a triple axle trailer with electric over hydraulic drum brakes has little to no delay when used with a quality controller ?



My situation: I have a Max Brake controller in my 3500. My triple axle boat trailer has surge drum brakes on all 3 axles and I want to convert it to electric over hydraulic with a unit by BrakeRite or Dexter. I want to know if I should expect a delay, or if there is a brand that is better at limiting it, or if its a moot point because the Max Brake controller will minimize the delay to near nothing.



Thanks in advance.

 

[Slow Six]

Like C Denton I also have just purchased a new 36 ft. DRV. After a lot of reading here and on other RV sites I installed a Max Brake. We are just finishing our first trip with the new rig and I am really impressed with the braking. My wife has said numerous times how good the brakes feel and work. As for the delay yes there is a delay but it is ever so slight, in fact I find that I really have to be paying attention to the braking to notice it. I feel very confident in the brakes in all traffic conditions from interstates, hills and in heavy traffic such as Salt Lake City's I-15 with construction etc. IMHO it is a good system.

 

[HBarlow]

Harvey,

Just looking for some clarity on something :

would you say then that a triple axle trailer with electric over hydraulic drum brakes has little to no delay when used with a quality controller ?

My situation: I have a Max Brake controller in my 3500. My triple axle boat trailer has surge drum brakes on all 3 axles and I want to convert it to electric over hydraulic with a unit by BrakeRite or Dexter. I want to know if I should expect a delay, or if there is a brand that is better at limiting it, or if its a moot point because the Max Brake controller will minimize the delay to near nothing.

Thanks in advance.

TopGun,

No, my experience is that the opposite is true. The trailers I pulled that were equipped with hydraulic disc brakes had a disappointing delay before brakes were actuated that convinced me at the time that I had NO interest in owning a trailer with hydraulic disc brakes. The truck's brake controller cannot eliminate or reduce that delay that occurs during the time it takes for the trailer brake system to build up hydraulic pressure. The time delay is normally relatively short but when your speed is 60 mph or more and traffic or a traffic light has stopped in front of you and your gross combined weight is 24,000-28,000 lbs. one or two seconds of delayed brake application seems like a very long time.

My experience with hydraulic disc brakes on a large fifth wheel is limited to the trailers I pulled when I was a commercial RV transporter. I pulled new trailers from factory to dealers and once, on a particular Alfa with hydraulic disc brakes, I was forced by a brake failure to turn around and pull it back to the factory for brake system repairs then pull it a second time to a Texas dealer.

I should state that my experience with trailer hydraulic disc brakes has been limited to only those few trailers I was paid to haul. I have never owned a trailer with hydraulic disc brakes and do not remember the manufacturer's name on the brake system on the Alfas I pulled.

Tom Arnette brought the Towmaster hydraulic disc brake system to my attention when this thread was active earlier. Reading the information on that company's website leads me to believe that Towmaster uses a different and perhaps much better design that sounds like it eliminates the inherent delay I experienced and BG Smith confirms.

If I was looking for a trailer hydraulic disc brake system now I would thoroughly investigate the products offered by Towmaster. Their system MAY eliminate the inherent delay.

 

[Top Gun]

TopGun,



No, my experience is that the opposite is true. The trailers I pulled that were equipped with hydraulic disc brakes had a disappointing delay before brakes were actuated that convinced me at the time that I had NO interest in owning a trailer with hydraulic disc brakes. The truck's brake controller cannot eliminate or reduce that delay that occurs during the time it takes for the trailer brake system to build up hydraulic pressure. The time delay is normally relatively short but when your speed is 60 mph or more and traffic or a traffic light has stopped in front of you and your gross combined weight is 24,000-28,000 lbs. one or two seconds of delayed brake application seems like a very long time.



My experience with hydraulic disc brakes on a large fifth wheel is limited to the trailers I pulled when I was a commercial RV transporter. I pulled new trailers from factory to dealers and once, on a particular Alfa with hydraulic disc brakes, I was forced by a brake failure to turn around and pull it back to the factory for brake system repairs then pull it a second time to a Texas dealer.



I should state that my experience with trailer hydraulic disc brakes has been limited to only those few trailers I was paid to haul. I have never owned a trailer with hydraulic disc brakes and do not remember the manufacturer's name on the brake system on the Alfas I pulled.



Tom Arnette brought the Towmaster hydraulic disc brake system to my attention when this thread was active earlier. Reading the information on that company's website leads me to believe that Towmaster uses a different and perhaps much better design that sounds like it eliminates the inherent delay I experienced and BG Smith confirms.



If I was looking for a trailer hydraulic disc brake system now I would thoroughly investigate the products offered by Towmaster. Their system MAY eliminate the inherent delay.

Harvey,



Thanks for the response, though I mentioned I had DRUM brakes on my trailer, not disc brakes, and I thought you mentioned that a drum brake trailer will enjoy a shorter (if not non-existant) delay in having the brakes come on ?



TIA.

 

[Loren]

Harvey,

I have to comment on the disk brake delay since that has not been my experience. My 5th wheel is using a Tow Brake HD3000 with disc brakes & dual axles and on their web site (FAQ section) they have the following:



How fast can you get to full pressure?



The HD series can achieve full 1600lbs of pressure (for disc) in as little as 8/10s of second. That timing is to activate 6 disc calipers or 3 axles of brakes. For tandem axle disc systems the time to pressure is less than half a second. To reach full pressure on a drum brake system (1000 lbs) the time is a little over 1/2 second.



That . 5 second delay surprised me in that I have not noticed it when towing. But then perhaps 1600 lbs pressure is considerably more than what the majority of my braking involves. While I agree that any delay can be serious that does seem to be minimal. Do you agree? There must also be some delay with drums using other controllers as well, yes/no?

Thanks,

Tom

This manufacturer is claiming delays in the order of 0. 5 - 0. 8 seconds. It is undoubtedly no better than that.



To put these numbers into perspective, remember that 60 mph equals 88 feet per second.



That means you will travel 44 - 70 feet while you are waiting for the trailer brakes to apply.



– Loren

 

[HBarlow]

Harvey,

Thanks for the response, though I mentioned I had DRUM brakes on my trailer, not disc brakes, and I thought you mentioned that a drum brake trailer will enjoy a shorter (if not non-existant) delay in having the brakes come on ?

TIA.

Sorry, I scanned your original post too quickly and missed the details and then never saw this post. I let you down completely.

I don't think I have ever pulled a big trailer with hydraulic surge brakes, at least I don't remember the experience if I have, so I can't speak of my experience with them.

But since your post suggests that there is a delay in this system, which I would expect, I believe that removing the surge brake cylinder and converting to ordinary electrically operated trailer brakes with magnets and a high quality hydraulic over electric brake controller will eliminate the delay you experience.

 

[HBarlow]

This manufacturer is claiming delays in the order of 0. 5 - 0. 8 seconds. It is undoubtedly no better than that.

To put these numbers into perspective, remember that 60 mph equals 88 feet per second.

That means you will travel 44 - 70 feet while you are waiting for the trailer brakes to apply.

– Loren

Good point. The use of simple mathematics to answer ordinary life questions can often be very illustrative.

 

[Loren]

Good point. The use of simple mathematics to answer ordinary life questions can often be very illustrative.

Thanks Harvey. That's the best definition of engineering I've ever heard.



-- Loren

 

[tarnett]

Loren,
Prior to installing the Brakesmart controller I had used two others, including one recommended by a majority of posts in the RV.net forum. With both I would hear a clunk when braking that I believe was due to a variance in brake application between my pickup and trailer causing the pin to move within the hitch.
Once the Brakesmart was in and adjusted that issue was no more. Since the only change was with the brake controller it seems, to me at least, that both tow vehicle and trailer brakes are in sync. Having ridden motorcycles for 40 years in all types of weather and road/off road conditions I have a good feel for vehicle traction and feel comfortable in saying that my combination has very good brake control and feel.
One last point is that Tow Brakes delay time is for 3 axles and at a pressure of 1600 pounds. As mentioned that pressure is significantly higher than any reading I've seen on the Brakesmart. That along with two additional calipers will surely add to any delay.
One question I have not seen answered is what is the delay with drums. Surely there is some there as well.

 

[HBarlow]

Yeah, I'm sure there is some delay. Electromagnets, however strong, can't expand the brake shoes instantaneously, but for all practical purposes whatever delay actually exists in not noticeable.