GVM issues in tow vehicles

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Hi Folks,

Just thought Id open up a topic for discussion in relation to weight issues that many people encounter when towing larger caravans. Three weeks ago I had a long range fuel tank installed on my tow vehicle. I did a rough calculation on the extra weight that the full tank would add to the ute and was surprised at how close to GVM maximum I was going to be. After the installation, the ute was filled with fuel and packed with the gear that I was going to take away on a trip. With the coach sitting in the passengers seat, we went off to the local weigh bridge to get an idea of how we stacked up as far as weight was concerned. After adding the vans ball weight, I calculated that I had only 15kg up my sleeve if I was to be legal. That was a bit too close to the mark for my liking. If I throw a couple of slabs of beer in the back, Im over weight. Had to re- think weight distribution and packing to get a bit more breathing space. Even though the ute is rated as a one ton vehicle, every thing that you add cuts into that weight. A nudge bar, tow bar, canopy, drawer system, duel battery, fridge, tow ball weight, fuel, passengers and luggage all eat away at that magic number very quickly. If I had a bull bar and winch on the ute, I wouldnt be able to legally tow at all. Would be interested to hear peoples thoughts and creative ideas on this topic.

Cheers

Les
 
I'm just going though it now im bit sav,e with it being in the trucking industry im not too bad i got my caravan over engineered i got 800 kgs to play with tare 2200 gvm 3080 ball weight 180 kg but im doing my ute and missus car today ive got rough idea but i weight them both again but it looks not to bad "stay tuned"
 
Slightly different vehicle, we have a 1999 Pajero and I remove the back seat from the vehicle for our trip to the GT, all seats combined would weigh in at around the 100 kgs, gives a bit more room in back for detectors and other bits. Seats are replaced on returning home.Have a curtain that covers the items in the back from prying eyes.

Graham
 
I have found over the years that towing with a passenger vehicle , you need to have some sort of ride assist to level out and distribute the weight when towing.
I have towed a caravan to Ayres Rock from Melbourne with an old XD falcon ,my Dad did it in an old XY when they were a new car when it was all dirt roads and i have towed numerous ,fully loaded car trailers with 4WD`s and cars that had a fair bit of weight on them.

I got busted in NSW a few years` ago being over weight using an old XB falcon to tow a car trailer with my Torana show car i had to the summernats.
They wacked the tri - axle trailer on 3 sets of scales and we were a couple of hundred kgs over weight. Got fined for that and also having no rego sticker on the trailer, even though it was hired. We also had 4 blokes in the car ,so there was alot of weight all up that we hadn`t considered. A talk from the nice highway patrol officer gave me a new perspective.
I never tow anything heavy like that without a 4WD nowadays.

With a passenger vehicle , either pump up air shockers or a good set of airbags or extra leaf springs or override springs in the back are a good thing and really do help. Definately use sway bars when towing a caravan.


With a 4WD , they tow better ,due to having a full chassis ( the older ones i drive do , at least ) . The full chassis distributes the weight more evenly and the bigger wheels help everything roll easier and with less effort. I have got leaf springs and airbags in the back of my 4WD ute. The difference is that having no air in the airbags for regular driving keeps the vehicle just above level on the road and it rides nicely, using the leaf springs only. Put a decent load on it
( without a trailer ,just stuff on the tray )and the nose of the ute goes up and effects the steering. Very dangerous and illegal. Pump air into the bags and the whole scenario changes again. Using both the springs and airbags allows me to load the ute up and tow a full laden trailer with full control and i am always under weight.

I hope this info is useful to someone.

FOZ
 
Another think that you need to take into account, the seating capacity on manufacturer plate. If it says 5 people then for each unoccupied seat you need to add a further 80kg. Even if you have goods occupying those seats.
 
Your problem is very common, a couple of Christmas' ago the Victorian authorities had a blitz on caravaners, more than 60% were overloaded and I think the worst was around 600kg over.

When we had our MDC Cape York, we did a lot of work re-orientating the weight distribution and just managed to get it legal fully loaded :power: , the tug was a 2007 Patrol which is only rated for 250kg ball load. On our first loading the MDC was over 300kg hitch weight with a full water tank (behind axle).

Another problem with excessive weight in the back is the re-distribution of axle loads, manufacturers have a ratio or somewhere around 60-40 front to rear to maintain steering, braking etc, airbags etc DON'T change this but load levelers do, and the change in driving dynamics with and without levelers is dramatic. Trouble is you're not supposed to use load levelers on dirt and this is where steering dynamics is the most critical.

A client of mine imports the big Yanky trucks and his market is growing with the increasing popularity of the big vans, they can handle the big loads plus luggage, whereas the much vaunted 1 tonners can't and are often under powered as well, too much marketing BS and not enough real-speak.

Try talking to the sales people at car a caravan shows about this issue and watch them squirm!

Another problem is vehicle modification rules vary between states, so you can be legal in QLD but illegal in NSW etc, this is something the Caravan Association is tackling.
https://www.caravanindustry.com.au/...ralia-clarify-current-4wd-upgrade-rule-status

Staying legal and towing is becoming a minefield :(
 
Over here my Challenger can gross about 2500 I think can't remember but when Towing the GCM Gross Combination Mass is about 5700kgs which means I can Tow about 3 and a 1/4 Ton, but I don't think I'd ever put 6 or 700kgs in the Truck, Maybe 2 or 300 but not up to its limit,

The crazy thing about it the hand book says 1200kgs for the front Axle and 1600kgs for the rear axle and I=that it can Tow 2800kgs, But on the compliance plate in the Engine bay it says 5700 +/-, But it also says its weighs 1800/1900kgs, that's all very well but I can see it having a pay load of 900/1000kgs having axle weights of 1200 and 1600kgs, The chassis plate says 5700 and the truck weighs 1800 to 1900 empty means I got 3800kgs to play with shifting some of that 3800 In to the back of the truck, So say 600 kgs that still leaves me 3200 kgs to play with.

A 3200kg Caravan it a monster of a Van and well over 26ft/8m+, Add the Draw bar and the Truck that's about 45ft long, The down side to a Caravan that length is it's massive overhang at the rear, It also says the maximum noes/Tow ball weight 115 kgs, So with careful planning If I gross the Truck at 2500kgs that still leaves 3200 to play with. I don't Trust the hand book because I don't think it is the original one for the Truck so I go by the Government Compliance Plate under the Hood.
 
These are the Specs on my Colorado 7
1553909782_coll-fs.jpg


The interesting figures are; (and typical in most vehicles today)

The difference between GCM and GVM is only 2880, so if at GVM I can't tow 3000kg
The Front Axle Max + Rear Axle Max = 3050kg, which is actually 230kg more than GVM. (Interesting)

Example - If I tow a 3000kg ATM van and say the ball is 250kg of that 3000kg. This means the van wheels weigh 2750kg.

Next - The car GVM is 2820, but I need 250kg for the ball, so my new GVM before I add the van is now 2570kg.
The kerb weight (as new with fuel) is 2175, so the difference is 395kg. (the original load max is 645kg)

Next - I have an Engel, Aux Battery, drawer storage, contents and a towbar @ Total of 200kg in the rear. Which leaves me 195kg
When I prospect I carry a genny and detector gear I know weigh in the order of 60kg in the car = Balance of 135kg.

I weigh 70kg = Balance of 65kg - So the navigator needs to go on a really drastic diet or she stays at home :)

Conclusions
- Although rated at 3000kg, I can't tow that with my set up.
- If you have a bull bar, tow bar, roof rack and fridge in your 4x4, serious thought needs to be given to what is towed.

NB - My van is rated to an ATM of 1800kg and I am really pushing my limits at that load. I'll example why in a further post.
 
Yeah it's totally Nuts, Mine does not make sense either, My truck weighs around 1800kgs and the GCM on the plate says 5700kgs which leaves 3900kgs going spare But when loaded the hand book says about 2510kgs means I can Tow 3190kgs yet the hand book says 2800kgs,

2800kgs + 2510 Kgs is 5310, Yet the Government compliance plate says 5700kgs, Luckily the police go by what is on the compliance plate So 5700kgs it IS.

Crazy part is Is the Ball weight being 115kgs which is bugga all really,

On a side note you can get Caravans UP Plated so if you want to carry more gear in it you can, But that can be either a Tyre Upgrade or a spring upgrade or Both. Normally this involves taking the caravan back to the people who made it and for a small fee they will fit it with a new compliance plate that lists the new weight specs and possibly the up grades,
 
be careful taking seat out i took a seat out of my kenworth Sar to fit a fridge in no room in cabin replace all bolts back in the holes dont take seat belts out and tell them its only temporary or they bang u 4 it
 
I have never liked the idea of towing something that is heavier then the tow vehicle, if I was towing 3500kg I would be
looking for something that requires a LR license to drive.
My own combo is around 2500kg towed by a diesel grand Cherokee and it doesnt affect the car at all even when doing
130kph overtaking road trains.
I think the main thing that contributes to the stability of the outfit is the small distance from tow hitch to diff of less then 1000mm
where some of the twin cabs are more then 2000mm with a short wheelbase.

As for gvm issues they can be sorted, my work car has been upgraded from 3300kg to 4200kg, however expecting what is
essentially a light duty Ute to work like a truck is never going to be a long term solution.
 
One thing I have notice is that a lot of Utes/Duel Cabs can only Tow 2000kgs yet the same Truck in an SUV can Tow 3300/3500kgs, Which is another reason I went with the Challenger type body.
 
madtuna said:
The joys of remote WA...most people don't even worry about rego!
Not sure what what my perentie can legally tow but I know it can skull drag four dead camels in one hit without working too hard:Y:

Swap camels for buffalo and that is a common way to make a fire break in Arnhem Land, totally amazed me the first time I saw it being done
 
Ridge Runner said:
One thing I have notice is that a lot of Utes/Duel Cabs can only Tow 2000kgs yet the same Truck in an SUV can Tow 3300/3500kgs, Which is another reason I went with the Challenger type body.

If you look at the current range i.e. Ranger or Colorado etc. The Ute version tows 3500kg. The Everest or Trailblazer are rated at 3000kg tow. So the SUV is rated 500kg lower. Although the same engine etc it is down to the fact that the ute has wishbone springs in the rear and the SUV has coil. The Navara/Pathfinder and other brands are similar.

Re the 7 seats - most SUVs, like my Col 7 are 7 seat. I took the 3rd row out, used the seat mount points to make a false floor, to which everything else fits. The seat belts are still there. Although I will probably never drive the car with 7 seats, I claim it as a temporary modification and at some point in the future when I sell it, I'll refit the 3rd row and return the vehicle to OEM.

As an aside, I listed all the mods with my insurance company and noted the 3rd row removed as a temporary mod which they accepted.
 
condor22 said:
Ridge Runner said:
One thing I have notice is that a lot of Utes/Duel Cabs can only Tow 2000kgs yet the same Truck in an SUV can Tow 3300/3500kgs, Which is another reason I went with the Challenger type body.

If you look at the current range i.e. Ranger or Colorado etc. The Ute version tows 3500kg. The Everest or Trailblazer are rated at 3000kg tow. So the SUV is rated 500kg lower. Although the same engine etc it is down to the fact that the ute has wishbone springs in the rear and the SUV has coil. The Navara/Pathfinder and other brands are similar.

Re the 7 seats - most SUVs, like my Col 7 are 7 seat. I took the 3rd row out, used the seat mount points to make a false floor, to which everything else fits. The seat belts are still there. Although I will probably never drive the car with 7 seats, I claim it as a temporary modification and at some point in the future when I sell it, I'll refit the 3rd row and return the vehicle to OEM.

As an aside, I listed all the mods with my insurance company and noted the 3rd row removed as a temporary mod which they accepted.

Over here only this last few years they have started to give Duel Cabs a proper Rating, and also if you got your licence before 97 you can Drive a GCM of 8250kgs but if you got it after that then you are limited to a 3500kgs Trailer/Caravan and GCM = Car and Caravan weighing no more than 7000kgs,

Speed is another issue, On Major roads you are restricted to 50mph/80kph and on Motorways etc you are restricted to 60mph/98kph and if there are 3 lanes you can only use the first 2 and if there are 4 lanes in either direction you can only use the first 3,

You would be surprized how many people here who can't back a Trailer, Lol.
 

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