the towed vehicle must be braked in accordance with it's weight capabilities and tow vehicle restrictions

either the trailer or the vehicle combination must have tow vehicle actuation brakes,

normally the two wheeled trailer has the brakes but in some cases the vehicle being piggy backed must be braked as well, depending on weight of piggy backed vehicle

ah now you've got my weak spot (one of many) apparently there is an electronic "actuator" that somehow attaches to the rear brake setup that is installed, now this I don't know of but it only comes in where the weight is considered "excessive"

whether the 3 tonne weight of the patrol exceeds this with a braked dolly or not I am not sure, perhaps an inquiry to the motor vehicle department

I would think, given my limited knowledge on this, that the braked dolly would be sufficient, assuming the dolly was constructed of heavy truck like materials

our workshop here is not equipped to deal with this and our mechanics don't know how they do it either,

one suggested a simple pulling device that activated the handbrake cables on the towed vehicle??, without ratcheting on of course

Found heaps on the net on the topic  all States basically say  the following which is a extract from the  SA Fact Sheet on A Frames

If I'm reading this right  the towing vehicle mass must be 3.5 times greater than the towed vehicle.  I would assume a  Bus / MH and a Patrol would be okay on an approved "A" Frame without actuated  brakes on the towed vehicle .


As a safety precaution, the
combination shall have a towed mass
ratio of at least 3.5:1 that is, the
mass of the towing vehicle must be at
least 3.5 times the mass of the towed
vehicle. This ratio is to provide for
adequate levels of vehicle stability,
handling and braking performance.
Braking requirements
The requirement for a 3.5:1 towed
mass ratio is designed to give a
combination adequate braking
without the need for the brakes of the
towed vehicle to be operated by the
driver seated in the towing vehicle.




-- Edited by Wombat 280 on Saturday 25th of April 2009 12:23:02 AM

dave06 wrote:

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so that would mean that the bus would have to be 10.5 ton to be able to tow a 3 ton nissan without brakes

---

Not sure what the weight of a average MH / Bus  is  but if it's the big bugger that comes in at about $800.000.00 then I would expect 10.5 tons is about right for an all up prime mover  weight  ..

If I had  the 800,000 then towing a second vehicle would be a  waste of time I'd  just hire one when I got  there .

I think a patrol is an over kill by a suzzi  on an "A" frame may be more near the mark for most MH/ Bus

One other thing that came up in reading the regs , It's illegal to have a tow bar protrude beyond the vehicle body  when not actually towing something   . The regs  up till recently only stated that the towbar  shall not obsecure the number plate when not towing something .  That pic of the bike rack I posted a few weks back is certainly out in that case