Towbar confusion?

The friendliest place on the web for anyone with an RV or an interest in RVing!
If you have answers, please help by responding to the unanswered posts.
Mark R. said:
Sorry Bernie but I must disagree, sprung weight when talking about a vehicle is the weight above the suspension springs, unsprung weight would be the tires, wheels and axle.

Mark

Isn't that what I said, but with slightly different words??? The weight above the suspension is the weight supported by the suspension.

The braking and inertia issue would be due to the brakes on the RV being applied while the toad was still free wheeling. Without supplemental brakes, the toad's inertia continues pushing on the hitch while the brakes are slowing the RV.
 
I think Mark's point is that both sprung and unsprung weight contribute the same mass to the inertia, so it makes no difference when accelerating or decelerating.

If the combined weight of coach and toad are less than the coach  GVWR, then the coach brakes can handle it. But the coach will still stop faster (shorter distance) if the toad has its own brakes. Stopping a large vehicle in a shorter distance is always a wise thing!
 
Bernie I must have miss understood you, thx Gary and yes all toads should have brakes in my opinion!
 
What if the toad brake system fails and applies the toad brakes unexpectedly and causes a wreck.  Am I going to get sued for reckless endangerment because my "toad brake" worked when it should not?  Or if the connection between the MH and the toad is severed and the toad brakes are applied?  I wonder how many single point failure modes there are in a toad brake system that could cause the brakes to activate when they shouldn't. compared to the likelyhood that the toad brake system will work and provide the margin of extra braking power to avoid a wreck.  I bet I could think of at least a hundred failure modes where the toad braking system could fail either on or off.

Sometimes I think that all these belts and suspenders systems, especially active systems that are supposed to turn "on" when they fail are worse than no system at all, especially if a failure could cause a wreck.  Seems like, for many situations, the best outcome is for the toad to stay attached to the MH no matter what and let the MH do its job, under control without some 4000lb tail wagging (with the brakes on) the dog in unpredictable ways.

I worked in weapon safety for a number of years and have seen the consequences of unexpected failure modes many times.  We had a cardinal rule that if something can fail, it will and when it does, it's better for it to be passive and predictable, especially when wrecks are factored into the equation.  I also understand that laws try to deal as best they can with unpredictable situations but no man made law will supercede the laws of physics in my humble opinion.


BTW: here's a website that lists the requirements by state:   http://home.roadrunner.com/~morodat/toad-brakes-by-state.html
If this is accurate, I'd say that most states, except Florida, Nevada and Alaska and a few others, agree with me, get a brake system if you need it to me the performance requirements.  Guess I won't visit Florida with a toad unless I have a brake buddy... I wonder if I have to prove it actually works?

You'd be much more likely to find drivers without a proper driver's  license than a MH than can't stop in 30-50 ft from 20 mph, again, IMHO.


thx, Gary
 
I will give you a truth table for towed brake system failures

The brakes SHOULD come on under two conditions

1: If the towed, separates from the towing vehicle.  (Break-a-way)  Yes, this may indeed cause an accident, but if you did not have towed brakes,,, There would still be an accident
With the brakes suddenly locking up the towed may flip and roll, but odds are, if you are on the freeway, it will stay on your side of the median,  Thus when some idiot who is following way too close slams into it it will be a low-speed-differential accident and survivable

Without towed brakes it may well run through the median and do a head to head with a car going the other way, over 150 MPH speed differential and.. Multiple fatalities.

2: When you apply the motor home brakes: Normal operation. No problem.


Now, what happens if it faults and locks 'em up when it should not:  Answer.. Your towed catches fire, there is no multi-vehicle accident, as the other drivers (If that is they have a working brain cell) will avoid the flaming towed ... With luck one of 'em will buzz the Fire Dept and they will hose her down before your motor home catches,, but I'd not count on that.

However, the damage will be all to your vehicle, no other, and if there is any legal action it will be between you (As plantiff) the insurance comany (Hopefully joining you) and the manufacturer OR installer of the brake system.
 
Gary, I can't address all your questions and comments since they range from the rhetorical to the ridiculess.  However, some of your statements clearly indicate that you don't fully understand the purpose or installation chatacteristics of the supplementary brakeing systems.  EXAMPLE...
Seems like, for many situations, the best outcome is for the toad to stay attached to the MH no matter what and let the MH do its job, under control without some 4000lb tail wagging (with the brakes on) the dog in unpredictable ways. Gary

This is exactly what every system manufacturer and user hopes will happen (in every situation).  However, if the hitch does fail, the safety cables or chains are in place to prevent a complete break away.  Now, heaven forbid, if both those items fail, and a complete separation occurs, the breakaway cable is designed to activate the loose toads brakes.  This is the safest and most desirable outcome in this scenario.

With a properly sized and installed breakaway cable the toads brakes should not lock while the safety cables are still securely attached between the MH and toad.  I don't understand how your "tail wagging" situation could occur.

BTW - there is not a lot of complicated circuitry involved here.  I seriously doubt your ability to find that one-hundred failure points.  

I'm constantly amazed by the number of people more worried about their ability to tow their toad up hill at 70 mph than there are who have any concern at all for getting it stopped.  
JMHO...
 
I would never recommend any supplemental braking system that doesn't give a positive indication of when it's been activated to the motorhome driver.  That's why I will only use a system that acts directly on the towed brake pedal and uses a radio transmitter connected to the brake lights switch to send a signal to the driver every time the brakes are applied.  Then, if the brakes to lock up due to a failure, the driver will be notified and can pull over and stop before damage occurs to the towed vehicle.  Not all braking systems can be so configured.
 
Ned I have a visual indicator for a brake lockup situation on the toad, no radio needed, and can be used on any toad/MH combination. Two weeks ago coming home from vacation towing my toad (1967 Fairlane 500 wagon) I had to make a shorter then normal stop, not a slammer or anything like that,  I had someone following me and I did not want them to run the light to stay with me , so I got on the brakes just a bit harder then normal.  In a matter of a second or two the locked wheel indicator's came on, in the form of blue smoke pouring out from both sides of the motor home and  loud tire screeching, the smoke was easily visible in both mirrors and the backup monitor! I was asleep at the switch you could say since I have a switch on my dash that shuts off the brakes to my toad, or  I could have reached down and dialed down the gain on my Prodigy, but I just was not ready for the situation. Why was the controller set so high one might ask, well I love this controller and have two of them that I use in my four tow vehicle's,  I removed this controller from my wifes Suburban just before we left on vacation with the MH, she had been towing our horse trailer and the gain was set for that trailer, which takes more power then my toad. Needless to say I have now added a new line to my toad hookup check list, "adjust brake controller". The car tracked true behind me as the tires were completely destroyed in one stop.

I never have heard of brakes failing and turning on, not to say it could not happen, but power would have to go to the brake hot wire.

Most high end controllers test the circuit constantly and indicate on he controller if all is well.

My 5100lb toad did not wag my MH, I got two black lines on Rt 113 in Maryland to prove it.

 
If you rely on the smoke and flames to tell you your towed brakes are locked up, it's too late :)

Yes, I have had the towed brakes lock up and we caught it by the red light on the dash.  We use a brake system designed for towing a vehicle, not a trailer, so there is no controller in the motorhome.
 
All I can say... if we designed our weapon safety systems the way the toad brake systems are designed, we would lose a lot more aircraft and other war fighting machines before they ever reach the war zone.  A vehicle in motion (i.e., with a lot of kinetic energy and momentum) is, in some ways, like a weapon.  It's not designed to destroy targets per se but it certainly has the capacity to destroy things in a wreck, for instance.  If you accept that propositiion, then the design of the safety systems is more reliable if they are passive and fail safe as opposed to active and fail in an unpredictable way. 

Ned said: "Yes, I have had the towed brakes lock up and we caught it by the red light on the dash."  What if the bulb failed, or the sun was shining just at the right angle to not see the bulb, or the wire shorted out that brings current to the bulb, or the power supply that powers the bulb, or probably many, many other components that have to work to cause the light to come on... this is an acitve system... lots of components have to work for this system to work.  Then there's the oppostie failure, the light comes on but the brakes are not on so Ned thinks the brakes are on and takes emergency action in response, unpredictable outcomes to a false positive light bulb.  Compare this complex and uncertain system to a passive system that is engineered to make sure that the toad stays attached to the MH no matter what... as best as the engineers can do.  The system is passive and has fewer failure modes and remains predictable. 

another quote for example: "only use a system that acts directly on the towed brake pedal and uses a radio transmitter connected to the brake lights switch to send a signal to the driver every time the brakes are applied."  I can only guess how many ways to spoof this system... a  radio transmitter in series with a safety system???? Most radio transmitters can fail  to transmit or not for many reasons.  Transistors, printed circuit boards, connectors, switches, capacitors,  all have to work perfectly as well as a radio receiver on the other end.

Another quote: "However, if the hitch does fail, the safety cables or chains are in place to prevent a complete break away.  Now, heaven forbid, if both those items fail, and a complete separation occurs, the breakaway cable is designed to activate the loose toads brakes.  This is the safest and most desirable outcome in this scenario."  Maybe so, maybe not... if the breakaway cable breaks (and it is far more likely to break than the hitch or the chains) and the brakes are slammed on, the situation becomes unpredictable very quickly.  The chances that both the hitch and the chains fail is way lower than the chance that the breakaway cable breaksl, but a broken connection of an electrical wire can suddenly turn the situation into a hazardous situation at best.  Without it, the brute strength of the hitch and two chains are passive and far more reliable from a safety perspective.


I don't know...  I guess it's up to each person to decide how best to operate in a safe way.  I just worry that the marketing department of the toad brake systems companies has sold the MH community a, what would you call it, a false sense of security.

I will say no more but thanks for reading... I do think it is important.  G.
 
I think I'll just stay in my recliner as there are so many ways I could be hurt just by moving around that it's not safe to do so.  Maybe I can arrange for intravenous feedings, but they might fail too.  Gosh, I feel so helpless :(

I'm so glad I'm not paranoid.
 
In all seriousness, do you have anything constructive to add to this topic?

Would you prefer a system that by design, won't notify of a brake application over one that will, even though the odds of a failure of that system are finite, but very small?
 
taoshum said:
I don't know...  I guess it's up to each person to decide how best to operate in a safe way.  I just worry that the marketing department of the toad brake systems companies has sold the MH community a, what would you call it, a false sense of security.

I don't think it's marketing. I will continue to use a toad breaking system because IT'S THE LAW IN MANY STATES AND CANADIAN PROVINCES! I'm not going to try to remember which states and provinces I'm required to have one and which I'm not and I'm not going out of my way to drive around those that require them. I also don't have the thousands of dollars it would take to prove I'm right in a court of law.

And I don't accept the argument that a toad isn't a trailer. There isn't a first year law student out there that can't convince a jury that there isn't an ounce of difference between the two.
 
I worked in weapon safety for a number of years and have seen the consequences of unexpected failure modes many times.

Oh, were you the guy that was responsible for making the Taser gun such a safe weapon?  :p :p 

Just kidding, but doing nothing to supplement your MH's braking system is not an alternative today when traveling in states that require it.  You're right that there are no supplemental braking systems that are fail safe, but that doesn't mean that we shouldn't use them.
 
Ned can you apply the brakes on your toad from your MH, without using the brakes on the MH? What system do you have and what  makes it superior to inertia or proportional control which as you say was designed for trailer brakes?
 
Mark, no, the towed brakes apply when needed, and only then.  I have the Apollo set to apply them only in a hard stop.  I see no reason to wear the brakes in normal stopping.  I've never said it was superior to any other system, but it works as I want it to.  A towed brake system isn't for stopping the motorhome, it's for stopping the towed vehicle, and ours does that very nicely when needed.
 
With the US-Gear system.. If the brakes are applied at the command of the control unit (IN the motor home) htere is a LED light bar that lights up red.. If the unit is in normal standby a Green light

If the towed brakes come on, for any other reason (IE: Break-a-way) The red LED bar comes on full and there is a LOUD STEADY BEEP,, ONly steady beep in the coach so I don't even need to scan for it, all the others go beep beep beep or some pattern of beeps. this one is bEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE.......P

IF the connection is lost (While the engine is running on the MH) You get a long BEEEEEEEEEEEEEEEEP, again, longest beep in the MH, but instead of the led bar coming on full, the green light goes out.

Very good audio feedback
 
Well I guess it comes down to personal preferences, I like to be able to apply the brakes on my trailers (and I consider my toad a trailer if I am pulling it) for a host of reasons , such as going down hill its nice to be able to add some braking at times , during bad road conditions , wet, ice, snow (I tow year round), and if I have a tow vehicle brake failure I have a backup when I need it most.
As far as not using the toad brakes , you pay to stop either way, brake pad usage will be increased on MH if not on toad (no free stops). In NY any trailer over 1000 laden weight needs brakes and over 3000lbs requires cab controlled brakes (so I have been told).

I looked at the Apollo wed site and it appears that it is what I would consider a "dummy unit", just applies a fixed amount of pressure (set by owner) if a inertia switch senses a stop, useless in an emergency, but it is easy to install.

 
There is no way that the towed brakes could stop the motorhome so that possibility is moot.  The motorhome brakes will last a lot longer than the towed brakes, I doubt we'll wear them out in our lifetime.

The Apollo does work by applying the towed brakes when it senses sufficient deceleration, set by the sensitivity control.  I have it set so it only applies in a hard stop, which includes emergency stops, just when it's needed.  That's far from useless, especially in an emergency.
 
I looked at the Apollo wed site and it appears that it is what I would consider a "dummy unit", just applies a fixed amount of pressure (set by owner) if a inertia switch senses a stop, useless in an emergency, but it is easy to install.

Mark, the "fixed amount of pressure (set by owner)" that you're referring to is equivalent to slamming your foot on the brake pedal.  The brakes are always applied quite forcefully on the Apollo and the sensitivity control that Ned was referring to only sets the condition for when the toad brakes are to be applied.

I don't know why you call it a "dummy unit", it actually is quite smart (with fast response times) in recognizing when the toad brakes are to be applied (based on the sensitivity setting) and then actually applying the brakes.  (Blue Ox claims it's faster than its competitors but that may be disputable.)  What really bothers me the most is the use of the word "proportional" in the literature describing these kind of supplemental brakes.  The only time these braking systems are truly proportional is during an emergency stop when the MH brakes are applied full force!!
 

Latest posts

Forum statistics

Threads
132,149
Posts
1,391,078
Members
137,871
Latest member
Katjarner
Back
Top Bottom