BT50 Boss suspension set up for a slide on camper

Hoyks

Well-Known Member
you’ll find that airbags replace the bump stops so it won’t be riding on them.
Thats my point, 30psi in those air bags is the same as driving around on the bump stops, just in this case they are adjustable.
 

cam04

Well-Known Member
Thats my point, 30psi in those air bags is the same as driving around on the bump stops, just in this case they are adjustable.
Roger. I’ve got your point now. I’m way too literal sometimes.
 
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Randal Canning

New Member
May be standback and have a good look at it. Does it really look, feel safe on the road ? going by your description you have exceeded the vehicles limits by a lot. 500kg on the tray that's asking for trouble and where is the sprare on the bullbar if so that may be illegal and helping to add more stress to the chassis so be prepared for it to bend or snap one day.

Seriously your set up sounds very dangerous you may need to get a different vehicle like a single or extrcab or get a chassis extension done to get the rear axle near the centre of the tray so you don't need massive springs to try and compensate for a poorly set up vehicle.

Any company that suggest a spring upgrade will help are dangerous fools. Do the right thing and fix the issue correctly befoe you have anaccident and injure or kill yourselves or other innocent road users don't kid yourself that it can't happen. Sorry I don't mean to jump down your throat but don't like dangerous vehicles on the road.
May be standback and have a good look at it. Does it really look, feel safe on the road ? going by your description you have exceeded the vehicles limits by a lot. 500kg on the tray that's asking for trouble and where is the sprare on the bullbar if so that may be illegal and helping to add more stress to the chassis so be prepared for it to bend or snap one day.

Seriously your set up sounds very dangerous you may need to get a different vehicle like a single or extrcab or get a chassis extension done to get the rear axle near the centre of the tray so you don't need massive springs to try and compensate for a poorly set up vehicle.

Any company that suggest a spring upgrade will help are dangerous fools. Do the right thing and fix the issue correctly befoe you have anaccident and injure or kill yourselves or other innocent road users don't kid yourself that it can't happen. Sorry I don't mean to jump down your throat but don't like dangerous vehicles on the road.
I am not surprised your front end is up in the air and the car feels floaty. The rear end of the chassis is being levered down behind the axle. No amount of stiffer springs, air bags or blocks of wood between the axle and the chassis is going to fix it.

You have been thinking about weight, and your car may be under its maximum legal weight, but have you thought about mass and it's location in the car?

Mass is the amount of material in something. You could place a brick on a beer glass and it won't break but drop it on the glass and it will. The weight of the brick did not increase. The glass broke because the material in the brick fell, built up momentum, and hit it with considerably more force than it was applying when it was stationary.

When your car is in motion, particularly on uneven surfaces, the axle is going to be constantly rising and falling rapidly. Imaging the stress on the end of the chassis when it has to instantly lift that material or catch it when it falls and instantly heave it back up again. To make matters worse, the forces going up into the chassis increase by the square of the speed.

The internet is full of incorrectly loaded cab chassis utes with bent chassis. You will almost certainly join them if you keep driving with you car loaded that way.

Your other problem is handling. You car has been designed to run out wider at the front if you go too fast into a corner or swerve suddenly. With all that weight on the rear axle, you are in with a real good chance of having the rear going first and the car spinning around and facing the opposite direction, that is if it does not roll over.

The front or rear sliding first is known as understeer and oversteer. Tyres distort when any side pressure is applied to them. An angle known as the tyre slip angle forms between where the wheel and the tyre is pointing. The car will understeer if the front angle is higher than the rear. If the rear is higher, the car oversteers. The front to rear tyre slip angle ratio is controlled mainly by suspension design, weight distribution, tyre size/design and tyre pressures.

Another thIng to worry about is the axle housing, wheel studs, wheel bearings and wheels. If any of them break, you will be a long way from being the first to have that happen out in the bush.

Unfortunately dual cabs can create a lot of problems when family's load them. They usually know the car's fully loaded weight but they don't realise that a large percentage of that weight has to go in the seats. They were designed to carry five average weight men (currently 87 kg) not five jockeys or five teenage Asian girls. The result is often a car with the back dragging on the ground and the front up in the air although it is under GVM.
 

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discomatt

Well-Known Member
They are a fix/patch/botch up for a broken chassis, not a strengthening kit for a poor design as far as I am aware but I guess you could have them welded in before it broke but all that does is expose the next weakest point to an almost certain failure
 

Batts88

Well-Known Member
Hi All has any one fitted chassis brace repair plates as look like a good idea
It's still not going to help no matter how much strength you add to the chassis or how heavy duty the springs you put on the rear are when your load is behind the rear axle your front will always be light.

As an example my dual cab GQ patrol has 300kg rear coils to support the load which it done well because the axle is near the center of the tray but if the axle was in the original position I would need 500kg springs with air bags in the coils but the front would still be light because of all the weight behind the axle it's like trying to ride a sea saw when one person is much heavier than the other. The only way to fix it is move the heavy person closer to the center of the sea saw which is represented by the axle on your vehicle.
145ltr fuel tank
60lts water
80kg 2 spare wheels
120kg canopy
60kg aux batteries plus other gear.

20171205_130454.jpg
 
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Lost1?

Well-Known Member
Hi Randall, Appreciate you are seeking a low cost vehicle solution to your problem. However in this case an enduring, cost effective vehicle solution is unlikely to be cheap. Going back to an earlier recommendation of fitting the camper to a trailer is the best low cost suggestion to date. You could probably find a trailer chassis for about $2-3k. That could provide a base camp to operate from and do day trips. But you won't be doing the canning with a trailer.
 

Gidgee

Active Member
had been across Simpson desert and the Canning stock route.
Allso had a chat to active campers and informed me that they had fitted plenty to dual cabs.
Ask Mt Dare how many they recover each year trying to cross the Simpson, and how much it costs for the recovery. Getting away with doing something dangerous does not prove it's safe.
 
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