3Ton Towing rating my fat aunt!!.

Submitted: Tuesday, Mar 26, 2013 at 21:22
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This was discussed just recentley i know, but on a job site to-day a brand new Triton turned up towing a mini concrete pump.It had a long drawbar so all the weight was off the actual rear end of the vehicle, But i'm looking at this towbar mounted on such a miserable feeble bit of chassis rail with not even a cross member at the rear. thinking what about going uphill dead weight pull!!...Its all a sales pitch which could lead to a very unhappy ending with all this late model jap stuff IMHO.... The old defender is rated 3t towing capacity But i would never do it and its ten times stronger on the rear end than these late model things on the market at the moment...Now hiding around the back of the shed.


Cheers Axle.
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Reply By: splits - Tuesday, Mar 26, 2013 at 21:55

Tuesday, Mar 26, 2013 at 21:55
It is a bit hard to judge something like this just by looking at it. Maybe the factory approved tow bar doubles as the cross member. How the rest of the chassis performs would depend on how the load goes into it. Does it apply a bending force or a stretching force to the chassis or a combination of both?

The force required to keep it going up a hill may not be as high as one would expect either. A couple of months ago I decided out of curiosity to find out what was required to move my Lux in its unladen form. It weighs a little over 1700 kg empty. I put some bathroom scales up against the back of the tray and pushed on them. After a few attempts to make sure the readings were consistent, I found it only took 23 kgs to get it moving on the garage floor and 12 kg to keep it going along the driveway which has a slight up hill slope.

I don't know enough about maths to work out what would be required to pull 3 tons up a steep gradient at a given speed with a certain type of surface but I would guess it would be a long way short of 3 tons. The only way you would get that much on the tow bar would be to pick the front of the car up with a crane and let the trailer dangle below it.
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Follow Up By: Axle - Tuesday, Mar 26, 2013 at 22:07

Tuesday, Mar 26, 2013 at 22:07
Lol Splits maybe thats what they should do,Mate i'm old school what looks right usually is, but this later crop of tray back utes and their tow bars .........Don't look right!!.


Cheers Axle.
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Follow Up By: Nomadic Navara - Tuesday, Mar 26, 2013 at 22:54

Tuesday, Mar 26, 2013 at 22:54
Splits, you forgot the air resistance bit. If there was no air resistance then we would be driving vehicles with motors the size of a Victa lawn mower.
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Follow Up By: splits - Wednesday, Mar 27, 2013 at 10:18

Wednesday, Mar 27, 2013 at 10:18
Geez you are right Peter. No problems, I'll give Boeing a ring, they know a bit about air resistance. I'll then grab the Lux and the scales, recalculate everything, and get back to you.
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Reply By: Ross M - Tuesday, Mar 26, 2013 at 22:29

Tuesday, Mar 26, 2013 at 22:29
They will all move three tons but the ability to control 3T during the dynamics of driving and body movement over varied terrrain and emergencies is another thing altogether.
The rear ends on some "fat aunts" are possibly more substantial and solidly built too.
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Reply By: Rockape - Wednesday, Mar 27, 2013 at 07:06

Wednesday, Mar 27, 2013 at 07:06
Axle,
Don't be to quick to judge all utes. The Ranger/BT50 chassis is 5mm thick where the towbar attaches and extends well forward. The actual towbar forms the crossmember.

The towbar is 100mm box and the attaching plates are full gusseted.

Maybe there are structural failures of the towing system out there but I haven't come across any. Just had a look and the only one I came across was a towbar on. Wait for it. A Landrover.

Drawbar hitch

Sorry Axle.
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Follow Up By: Patrol22 - Wednesday, Mar 27, 2013 at 14:22

Wednesday, Mar 27, 2013 at 14:22
Seems the Prado folks have had some problems with using the factory hitch in combination with weight distribution systems too: Pradopoint
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Reply By: Member - Boobook - Wednesday, Mar 27, 2013 at 17:57

Wednesday, Mar 27, 2013 at 17:57
The tow capacity usually has more to do with the braking and suspension than the strength of the chassis. Pajeros can be 3.2T or more with no separate chassis.

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Reply By: The Bantam - Thursday, Mar 28, 2013 at 12:10

Thursday, Mar 28, 2013 at 12:10
Axle mate you are not alone in your suspicion about these rediculous towing capacities.

It is interesting how the practice of specifying towing capacity on pasenger and light commercial vehicles has changed over the years.

The maximum towing capacity for pasenger vehicles has always be calculated bassed on the unladen mass of the vehcicle......in the past it was no more than the unladen mass.....as you would see in the pre 98 hiluxes.....then it was changed to a bit more than the unladen mass as you would find in the 98 to 05 hiluxes.....now its a hell of a lot more.

It is also interesting how far some of the manufacturers are prepared to push the envelope.

A member on one of the other forums who was recearching the purchase of a new ute, gathered all the figures and posted up a spread sheet.
Toyota continue to be quite conservative, where some of the others are pushing the the envelope as far as the current regulations & engineering expectations will permit.

Some of the vehicles if you are to achieve "full rated towing capacity" the vehicle has to me more or less unladen.....well two large blokes and their lunch.
Where others, like to Toyota will carry at or near their full rated payload and tow their full rated capacity legally.

The expectation of towing 3 tonnes with a passenger derived vehicle that weighs less than 2 is plainly redicilous.

If you have reservations about the chasis strength.....they are very well founded.....there are dozens of pictures out there showing this latest batch of high towing capacity utes with bent rear chasis.....and it happens well and truly under towing capacity off road

OH and then there is the sneaky little slight of hand......lots of people are of the opinion than the ball weight should be 10% or even more, the current design expectation for trailers is as low as 5%.
Have a look at the maximum permissable down force on some of these high towing capacity utes.......they may indeed have high maximum towing capacities.......but in practice the maximum ball weight is the real limitation.

That is without considering the manufacturer requirement for load distributing hitches.

Remember too these are Maximums, permissable under the best conditions.

It might be fine to run maximum towing capacity 15 minutes to the local boat ramp or tip......but putting these vehicles on the highway maxed out is asking for trouble.....and don't even think about it off road.

OH remember the ball weight has to be deducted off the payload of the towing vehicle too.

Lots of people who are twoing what they think is legal...if weighed & inspected..would find themselves wearing a large fine, because they have taken the towing capacity at face value as a single figure.

cheers
AnswerID: 507726

Follow Up By: Axle - Friday, Mar 29, 2013 at 19:17

Friday, Mar 29, 2013 at 19:17
Could not agree more, mate!, But unfortunately its the salesman that does all the convincing these days.


Cheers.
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