Thread: New Towing Guides

As I said elsewhere, I think the new bit about requiring "D" shackles rated 1.5 times the ATM of the trailer is a great step forward. How many cars do you see with snap rings, or little padlocks attaching the chains and as for petrol stations selling tiny unrated "D" shackles IMHO it should be illegal as we know they will be used on trailers.

I find it interesting that Arthur Goddard's Hitchmaster D065 for the lunette ring on army trailers is in breach of the guide, because it requires a tool.

A further problem occurs when the shackle is rated at 1.5 x trailer atm.

the shackle pin becomes too large for the chain.

it is going to necessitate considerably larger size chain being fitted to most drawbars.

You guys are about 4 days behind the Grey Nomads Forum,, and I think you'll find its D shackles they are trying to get rid of,, replaced by rated BOW shackles.

if you read the pdf it says they prefer the bow shackle but d shackles are fine...

Originally Posted by ramblingboy42

A further problem occurs when the shackle is rated at 1.5 x trailer atm.

the shackle pin becomes too large for the chain.

it is going to necessitate considerably larger size chain being fitted to most drawbars.

I think the attachment point on the tow bar will be more of an issue than the chain.

Originally Posted by V8Ian

I think the attachment point on the tow bar will be more of an issue than the chain.

I have "Hammer-Lok" chain joiners on both my RRc and D4 because of the difficulty getting rated shackles into the car attachments.

After all for a 2Tonne trailer the shackles need to be rated at least 3Tonne and the only ones you can buy are 3.25T where the pin is 19mm and you need clearance on 27mm to pass the shackle through the chain or vehicle connection.

Does anyone know if the 1.5times is a combined total for both shackles or each?

If it were a secured load on a truck, its a combination of the restraints but the guideline is a little unclear on the shackles.

There seams to be a bit of confusion over shackle types and sizes. The way I read it is :

1. Bow shackles are preferred over D shackles purely because they provide a greater range of movement. Thats it.

2. The requirement for a specific shackle rating is for each chain connection. If a requirement exists for 2 chains (over 2500 kg ATM), then each must have the correct rated shackle.

3. Quoting from the Safe Towing Guide, "shackles should have a Break Load Limit of at least 1.5 times the trailer ATM. The Break Load Limit is generally 6 times the W.L.L. of the shackle." Using my 3T car trailer as an example -

An ATM of 3000 kg X 1.5 = 4500 kg "Break Load Limit"

A BLL of 4500 / 6 = 750 kg W.L.L.

So my trailer should have 2 shackles (1 per chain) rated at a WLL of 750 kg. This equates to a physical shackle size of 8 mm (grade 6). I actually run 12 mm on my trailer.

At first glance an 8 mm (rated) shackle seems a bit small, but are legal.

Clear as mud ?

Originally Posted by Lotz-A-Landies

As I said elsewhere, I think the new bit about requiring "D" shackles rated 1.5 times the ATM of the trailer is a great step forward. How many cars do you see with snap rings, or little padlocks attaching the chains and as for petrol stations selling tiny unrated "D" shackles IMHO it should be illegal as we know they will be used on trailers.

Safety Chain Connections (Shackles, Pins or Bolts)
The Department of Transport and Main Roads recommends that the shackles used should meet Australian
Standard AS 2741-2002 “Shackles”, or another equivalent recognised standard, and have a break load limit of the shackle is rated at least 1.5 times greater than the ATM of the trailer.

Have another read. QLD Main Roads only recommend rated shackles and only recommend that it is 1.5 times the trailer ATM.

They also talk of braking load limit NOT working load limit.

My guess is the person who wrote the guide ant no engineer!

Tony