Community Forums

George Z · 08-28-2012, 01:07 PM

I just can't get over the thought of my toad breaking loose and not having the auxiliary
brake system to stop it. 3800 lbs. rolling 40 to 50 mph against oncoming traffic, or into some store front, and the damage that could occur. What would we have left after that lawsuit.

tquarles · 08-28-2012, 08:25 PM

Not to interject too much fact, but thy physics says that the distance to stop if you brakes are strong enough to bring your tires to a stop (skid) and you either lock them up or stop just short of skidding will be
K * 1/2 * V * V * (Mrv+Mt)/Mrv

Where K is an ugly constant that involves the local gravitational constant, the coefficient of static (or sliding if you're skidding) friction of your tires on whatever kind of pavement you're on, etc.

V is your speed

Mrv is the mass (weight) of the RV, Mt is the mass (weight) of the toad.

Note that the important thing is the term at the end is the ratio of the total weight to the weight on the tires that are being braked.
The problem is that the weight of the the toad isn't helping to generate any stopping force because it isn't pressing down on any of the braking tires, but the force generated
by the OTHER tires still has to decelerate it.(i.e. it participates in the F=MA equation to determine how fast you decelerate, but not in the F=KM expression to generate the braking force)

You want the 30% figure mentioned earlier in the thread - take a gasser w/18000 GVW (typical ford chassis) fully loaded and tow a 5000 lb toad. 23000/18000 = 1.27 - it'll take you 27% longer to stop. Decide that since your toad is so heavy you'll stop short of the MGVW of your rig and only load it to 17000 lbs - now it takes you 29% longer to stop...

And your 30k lb diesel pusher isn't much better off - 35000/30000 = 1.16 - still almost 20% extra stopping distance, and they're usually rated to tow 10k, so some may have toads weighing considerably more.

You can argue about the laws of the state all you want, but the laws of physics don't care.

That's why I didn't tow until I had a braking system in the toad.

Sky_Boss · 08-29-2012, 08:13 AM

Quote:

Originally Posted by tquarles

...

You can argue about the laws of the state all you want, but the laws of physics don't care.

That's why I didn't tow until I had a braking system in the toad.

YA...What HE said!

JSBrosecity · 11-25-2012, 08:41 AM

It's the law in most states and foolish to tow without brakes on the toad. I did a bunch of research recently here in fall 2012. Camping World sells the Roadmaster tow bars and Brakemaster air brakes setup. I have been told that if your coach has air brakes you should not consider anything but air braking for the toad. A lot of people have been using Brake Buddy for years and I am sure it's a solid product, but state of the art today for a Country Coach with Air brakes is an air system... and SMI's Air Force One is the very latest technology. Unlike Brakemaster it doesn't apply brake pressure in the toad with brute force, something which can break the brake pedal saddle in your car.

If you have a heavy Toad with power brakes, you want to apply proportional braking and tapping into the Toad's vaccuum system to apply power brakes. Only SMI does this. And the relatively tiny piston it uses to apply pressure to the brake pedal is permanently installed and out of sight. Infinitely superior to Brakemaster in every way. I understand SMI had some design problems early on, but I have been told they have it under control now, and Hitch Pro in Eugene OR (MH Central on the west coast) says SMI Air Force One is the way to go. Because our Toad is a Chevy Suburban LTZ, we went for the 10,000 lb capacity Roadmaster All Terrain 2 and coupled with SMI's Air Force One, this is a superior towing system

jauguston · 11-25-2012, 09:49 AM

Having brakes on your toad is a very good idea - BUT - anyone that tells you it is the law to have them is just plain wrong. A toad four down is NOT a trailer and any regulation for trailer brakes does not apply. Toad brakes-GOOD-- Toad brakes legally required - No

The only known place that requires toad brakes BY LAW is the Provence of British Columbia and there tow brakes are required for toads over 2000kg (4400#).

A few States have a minimum stopping distance requirement but do not specifically say you have to have tow brakes to meet that distance.

There are several places on the internet with a list of States that require tow brakes and they are all put there by businesses that sell tow brake equipment. Not a reliable source of information.

All that said please don't tow without tow brakes.

Jim

YC1 · 11-25-2012, 10:26 AM

I towed a jeep, chevy blazer, explorer, all to Colorado from California many times in past years. I always had a shorter/lighter rv and never had any issues braking. I do use the tranny going downhill and drove at safe speed. My 05 Sightseer had crappy brakes so I installed the SMI system on my H3. Worked poorly but did work. It was in their early development and they did not work well with the hydroboost brakes on the H3. Todays models are excellent. That said I have installed a different model on my new Ford Edge.

Once I got my first toad brake I decided there was no other way to go. Even now that I have a large DP you can notice it if the toad brakes are not activated.

Old Dude 66 · 11-25-2012, 05:25 PM

SMI is not the only system that uses the car vacuum for power brakes! The US Gear Unified Tow Brake also has proportional power braking. Comes with a vacuum pump to replenish vacuum. Works great.

YC1 · 11-25-2012, 05:45 PM

Quote:

Originally Posted by Old Dude 66

SMI is not the only system that uses the car vacuum for power brakes! The US Gear Unified Tow Brake also has proportional power braking. Comes with a vacuum pump to replenish vacuum. Works great.

That was the problem, the H3 does not have vacuum assisted brakes. They are actually assisted by an electric pump. I found a way to activate the assist by installing a fuse holder. They sent a too large vacuum solenoid to pull the pedal down. Controlling the braking pressure was just impossible.

JSBrosecity · 11-26-2012, 07:42 AM

Yes Olddude, I did encounter US Gear's system when I was doing my research. I WISH I could remember where/what it was I saw that persuaded me NOT to go that route. I just did a little googling hoping to come up with something, but nothing jumped out at me. But something came up that sounded pretty dire to me to cause me to just write that off as a possibility. Maybe someone else came across the same thing and has a better memory than me. In any case I think my final decision was primarily influenced by Hitch Pro in Eugene which recommended the SMI Air Force One.

For those who don't know, Eugene/Junction City Oregon is like Ground Zero for the RV industry in the west. Country Coach Factory was here as was Monaco and Marathon Coach. There are probably more major RV dealers and related industries in this area than in the rest of the western US combined. Point being, that the advice you get here is second to none. I was actually at Guaranty RV/Chevrolet talking to them about towing and THEY recommended SMI... said they could put it on for me, but their service department was backed up and I could probably get it done quicker over at Hitch Pro... hitchproandtow.net. Hitches and tow bars is all these guys do and have been serving the RV industry for more than 10 years.

So when I went over and spoke with them they agreed that for my purposes, flat-towing a heavy Chevy Suburban LTZ 4x4, the Roadmaster All Terrain 2 and SMI AF One was the way to go. I realize that some businesses recommend the stuff they make the highest markup on, but these guys were cheaper than 4 other places I checked, so I think it was an honest recommendation. In any case the system is great. Probably US Gear is good too, I just wish I could recall why specifically I discounted that as an option.

JCM · 11-26-2012, 10:33 AM

Here is another reason for toad brakes.

Traps90 · 11-26-2012, 08:48 PM

Well we're definitely setting up our Jeep with brakes (SMI Air Force 1) I look at it as get it done and never have to worry about being legal or not anywhere we travel. Also been around long enought to know that they do make a difference.

Mr_D · 11-26-2012, 09:00 PM

Quote:

Originally Posted by jbrosecity

It Unlike Brakemaster it doesn't apply brake pressure in the toad with brute force, something which can break the brake pedal saddle in your car.

Federal Law requires the firewall and brake actuator parts to be strong enough for dead peddle stops. So far I haven't heard of a single such failure on any of the forums I am on.

Mr_D · 11-26-2012, 09:05 PM

Quote:

Originally Posted by jauguston

A few States have a minimum stopping distance requirement but do not specifically say you have to have tow brakes to meet that distance.

Washington, Oregon and California all have the performance specification, Oregon is the toughest and WA and CA are less. There may be other states with that type of requirement too, but these are the three that I have researched.

Craig_R · 11-26-2012, 09:08 PM

To answer the OP's question specifically, brakes! Not just brakes but also a break-away switch, just in case your toad decides to take it's own path without you.

If your coach has air brakes your best bet is an air activated supplemental braking system such as SMI Air Force 1 or M&G Engineering. That whole Brake Buddy thing is just way too much work.