Brake controller

[Tom'sRedwood38GK]

Hi all,

I have a question about brake controllers and really don't have time to dig into the sight for research.  Our 1999 Volvo Gen 1 VNL 610 came with a Hensley brake controller and I am running disc brakes on our 5th wheel which are electric over hydraulic.  The brake controller I have on the truck has a problem where it will not hold a steady voltage causing the the trailer brakes to pulsate.  I have a Prodigy 3 controller that is in my pickup I can use.  Can I just transfer it instead of purchasing new?   Could I ask y'all for some guidance if this will work or if I need to head in another direction.  I did put a resistor in the system to try to stabilize the voltage and amps to no avail.  Just trying to save some cash as my budget is starting to tighten up for the next few months.  Thanks in advance for your help........

Tom

[Mark and Dale Bruss]

The Prodigy and other inertia trigger brake controllers do notwork well with HDTs.  Because of the truck mass and the typical position of the trailer pin being behind the rear axle,  the controller doesn't sense braking well.

The ideal brake controller for a HDT is one that response to the service brakes of the truck and not deceleration of the truck.   The Hayes controller uses the air pressure of the service brakes to apply braking current to the trailer brakes.  The elegant DirecLink controller uses signals from the ECM to generate the braking current.  Then there is the BlueDot system where the Electric/Hydraulic servo is replaced by an Air/Hydraulic servo and the service brake air is used to apply the hydraulic pressure..

There are discussion on this in the Resource Guide and there are PDFs of the Braking presentations at the HDTRally found on the HDTRally.com site.

A brake controller is no place to skimp for a safe rig.

 

[rickeieio]

I agree with Mark.  This ain't the place to save money.  I went with a BluDot this past winter and love it.  About $650 for three axles w/ Dexter discs.

[GlennWest]

I also installed Bludot on our Teton. Some of the best money we have spent. The truck is designed for air brakes. Works so good.

[Ronbo]

I went with direclink and love it.

[Big5er]

3 hours ago, TomNGina said:

Just trying to save some cash as my budget is starting to tighten up for the next few months.  Thanks in advance for your help........

Tom

Tom, the best bang for the buck is the Hayes Air Actuated controller. 
Like Mark said, inertia controller just aren't any good on our trucks. 

THIS is the best price I have seen lately for one.

[GlennWest]

Hayes is supposed to be good. I never did get mine to work right. Thought it was brakes but they were good when I removed them. Resistance good on magnets too. Glad I have disc now though

[Tom'sRedwood38GK]

1 hour ago, Big5er said:

Tom, the best bang for the buck is the Hayes Air Actuated controller. 
Like Mark said, inertia controller just aren't any good on our trucks. 

THIS is the best price I have seen lately for one.

Thanks Phil they are pretty close to home will contact them and see if I can pick one up. Kind of a bummer that the Hensley that my truck came with is on the fritz. 

 

[SuiteSuccess]

Tom,

I know that Roadfitter had a new Maxbrake he was trying to sell.  Maxbrake is no longer being made or supported but I’ve had mine 9 years with no issues.  It is proportional like the Hayes.  Personal message me for his contract info if interested.

[Tom'sRedwood38GK]

25 minutes ago, SuiteSuccess said:

Tom,

I know that Roadfitter had a new Maxbrake he was trying to sell.  Maxbrake is no longer being made or supported but I’ve had mine 9 years with no issues.  It is proportional like the Hayes.  Personal message me for his contract info if interested.

Thank you for the information will check this out if my options of picking it up close fall through.

[noteven]

I installed a Hayes controller in my KW dually -  like - it does not have a CM of any kind to connect electronic controllers. . It is connected via the air brake system application pressure display circuit and is actuated by the foot valve or the trailer brake control valve on the column, "real truck style" 😎.  Old school hill start aide...

I had a Maxbrake in the won ton pickup. Liked. Until it failed one day and I did not like the braking capability of the won ton by it's own self  ...😨... the won ton sports a DirecLink now and I really like. Their customer service is exceptional. 

[COFLTravler]

I also have electric over hydraulic system in my RV.  I am planning to upgrade the unit in the next couple of years so did not want to install the Blue Dot system.  I went with DirecLink and in fact worked with them on a prototype cable for my truck as it is a 2014.  I have been very pleased with the system and it was not difficult to install.  I also agree - brake control is a key piece of the mods needed to pull safely with our rigs.....

 

Mark

[Tom'sRedwood38GK]

I would check out the direct link but I have a GearMaster 2 already using the computer port.

Now with the Hays controller being hooked to the air can I use the manual air lever to apply the brakes on the trailer instead of using the controller itself if it is hooked into the trailer air side?

Thank you everyone for your help.......

[Jim Gell]

Yes, the manual air brake lever works with the Hayes. I have a used one I would sell, but I must say that I took it out because I found it difficult to adjust . But then I am challenged when it comes to following  written instructions.  I may have just been been turning the knob the wrong way.  It was not intuitive for me. 

If you still want to buy my used one, PM me.

Jim

[Brad NSW]

Newbie here.  Installed the direct link in my "new to me" first HDT.

Install was simple, once I got the right power source.

It's easy to adjust with my new disk brakes on the 5er.  I've got great confidence over the previously installed controller.

Jackalope seems to like it.

Totally happy with it on two 3-400 mile trip in all kinds of SOCAL traffic.

[Darryl&Rita]

3 hours ago, Jim Gell said:

Yes, the manual air brake lever works with the Hayes. I have a used one I would sell, but I must say that I took it out because I found it difficult to adjust . But then I am challenged when it comes to following  written instructions.  I may have just been been turning the knob the wrong way.  It was not intuitive for me. 

If you still want to buy my used one, PM me.

Jim

Jim, I'll buy it, if no one else speaks for it. We're on the way to Alaska, wink, wink.

[Ronbo]

Brad you will find that you have a tendency to adjust the trailer brakes so you can feel them hit. That is what we did with out LGTs. That will wear out the brakes in about a year. Decrease the gain until you can tell that they are helping because of your decreased stopping distance and you will be set. My rev is 21,000 lbs and I have it set on the lowest setting for heavy trailers.

[Brad NSW]

Ronbo,

That make a lot of sense and is similar to what I did.  Knew if this "big" truck was "feeling" the little trailer tug, that was too much.  Adjusted it down until the brake pad temps on trailer were similar to those on the truck after pulling into a rest stop...then bumped it up a level.  If I remember right, it's on heavy trailer 2 or 3.. First hard stop when adjusting them, trailer left skid marks...went way down from there.   I also watched the hitch in my hookup camera and can tell when the trailer is doing more than the truck so that helped in backing it off too.

Like all of us, I let the engine brake do most of my braking but want the trailer gain to be there when needed, especially on wet or downhills.  Will be interesting to see how long the pads last.  May have to adjust more after observing that wear for awhile...but then pads are cheap too...hmmm

[RandyA]

On 6/7/2018 at 5:27 PM, Mark and Dale Bruss said:

The Prodigy and other inertia trigger brake controllers do notwork well with HDTs.  Because of the truck mass and the typical position of the trailer pin being behind the rear axle,  the controller doesn't sense braking well.

 

 

1

At the risk of opening Pandoras Box, I'm going to challenge this piece of HDT "wisdom".  I've been reading such warnings since I joined this group nine years ago.  They have always been the cause for some serious head scratchin'.  Now, I have the utmost respect and admiration for Mark.  He was and still is one of my go-to guys for information in the resource guide. I consider him to be an extremely smart man. Without his contributions, it would have been considerably more difficult for me to move smoothly to the dark side.  I am eternally grateful for his many works.

I sincerely hope my comments will NOT be interpreted as a hostile argument - they are not.  Rather, let's revisit this piece of HDT wisdom and see if it passes the Physics litmus test as true or false.

For my examples, we will use two different vehicles with their actual weights as they cross the scales:

1) Any HTD @ 21,000 pounds pulling a fifth wheel trailer that weighs 19,000 pounds traveling at a speed of 50 mph.  The hitch is mounted on the rear of the HDT.  The mass of this rig is 40,000#

2) Any LGT @ 7,000 pounds pulling a fifth wheel trailer that weighs 12,000 pounds at a speed of 50 MPH.  The hitch is mounted over the rear axle.  The mass of this rig is considerably less at 19,000#.

Both vehicles have "inertia" when parked or moving -   inertia is the resistance an object has to a change in its state of motion.   Now, the tendency of either rig to resist changes in its state of motion will vary with mass. Mass is that quantity that is solely dependent upon the inertia (resistance) of an object. The more inertia that an object has, the more mass that it has. A more massive object has a greater tendency to resist changes in its state of motion.

Now enter a couple of new terms:  Momentum and Velocity.  Momentum will be the mass of the HDT rig while it is moving and velocity will be the speed the mass is moving.  This is expressed as p=m x v (p=momentum).  Since we are talking about loaded, moving vehicles we can alter the formula to be p=lbs x mph.  The HTD momentum is 2,000,000 units while the LGT is 950,000 units or less than 1/4 that of the HDT.  So?????

Now comes the most important part.  We are going to require BOTH vehicles to come to a complete state of rest (stop) from a speed of 50 mph in a prescribed distance of 1,000 feet (a randomized distance).  Since momentum is a vector quantity, we will also assume that this is a perfectly level, straight line distance.  To come to a complete stop in this distance, the HDT will need MORE FRICTION than the LGT to overcome the difference in momentum.  The friction will come from the vehicle brakes and we will not try to get into discovering how much friction will be needed as it is irrelevant to the proof.  Assuming the needed friction is there for both vehicles to stop at exactly the same distance, BOTH WILL EXPERIENCE THE SAME GRAVITATIONAL FORCE (G-FORCE) to overcome their respective momentum.  Keep in mind the pendulum (g-sensor) in the Prodigy will be at "0 degrees" and appear not to be moving in either truck if you are inside the said truck.  But, to someone watching from outside the truck, the pendulum is moving at 50 mph.

And that is where I begin to doubt the concept of something like a Prodigy not working as well in an HDT as it may in an LGT of a lesser weight because of mass and hitch location.  The deceleration forces will be equal in either vehicle, the G-sensor in the Prodigy will record identical values in either vehicle.  Thus, the position of the hitch nor the mass of the HDT will have no effect on the performance of the device. (I still have not determined how the position of the hitch in relation to the axle should be computed - I'll save that for another day).

Now, all that physics stuff aside, comparing a BrakeSmart or a MaxBrake, even a Hayes air actuated controller to a Prodigy leaves out the advantages of having direct linearity to the exact air pressure being applied to the HDT breaking circuit and being passed on to the trailer brakes - even though any linearity will eventually show up in the sensor of the Prodigy a few slices of a second later.  The Prodigy will also show more sensitivity (sensor movement) from bumps and bounces that may change the sensation of altering forward movement than actual air pressure activation of the trailer brakes. Having used a Prodigy, Hayes, and BrakeSmart in our HDT I can honestly say that I have not noticed any appreciable difference in one controller over another to provide adequate, if not identical, braking distances.  Still, I prefer using my BrakeSmart controller because my seat-of-the pants feeling is that it does a better job of applying the trailer brakes at an optimum time and intensity due to varying road conditions and lateral movement of the rig.  Also, the Prodigy will not give me the date and time, wish me happy birthday or show a different devotional message every day like the BrakeSmart.

 

[Mark and Dale Bruss]

A lot of analysis.  While the truck and trailer are tied together, each can have its own momentum actions.  The effect of where the trailer pin to the axle affects the action of the trailer which will not be stopping as fast as the truck.  For a LGT and the pin being over the axle, the trailer, which usually outweighs the truck,  will push the LGT forward and downward pivoting on the rear axle.  That action will enhance the inertia change of the truck, triggering of the brake controller.

On the HDT with the trailer pin behind the axle, the action of the trailer, about equal to the HDT, will push down on the truck behind the axle.  This would act to counter the forward tilt the inertia controller is expecting.

The forward tilt during braking was well established in the early inertial controllers where level needed to be established.  The later versions now self level.

Then there is the empirical data from many HDTs not being satisfied with Prodigy and Genisys controllers providing braking for the trailer.

 

 

[Moresmoke]

I am currently running with a P3. My choice was based on cost and simplicity to install. I have not noticed any pulsing or other bad braking behavior. But honestly, my trailer is light enough that it really makes no difference.

I will know more in the next couple weeks as I get some mileage on a heavier trailer that has more effective brakes.

[Wrknrvr]

 One simple statement. With a HDT the brakes are only suppose to be used at a stop sign, or light.

 Or in an emergency situation.

 

 The engine controls speed otherwise.

 

 I use a prodigy and it works good. I have used electric brakes on construction trailers since in the seventies.

 I have electric brakes on a triple axle 24000 lb fifthwheel. Test the operation every time I hookup. With the hand actuating lever.

 

 I can see where time from the pedal moves until the brakes reacts cold be delayed. Also I think the prodigy will not register amps unless the unit is in motion.

 Just saying,    Vern

[rickeieio]

And slightly on topic, when using the engine to slow down, no warning is given to following drivers.  I have been told by the Bride, when she was following me, that I was nearly rear ended because I let the Jake slow me.

It might be a nice feature to have the brake lights come on whenever the Jake is activated.

[Mark and Dale Bruss]

Some motorhome diesels are set to have the brake lights activated by the Jake brake.

[Wrknrvr]

 That is a good thought Rick.

 

 I normally touch my brakes to activate the lights if things happen in a hurry for that reason.

 The other thing to do is use your 4 way flashers. 

 

 I see several petroleum tankers usually every day using flashers on the hills in Montana during my work travels. 

 

 Safe Travels,.   Vern