How good can a full-size solid axle suspension be?

Adventurous

Explorer
The other idea I have been kicking around is perhaps using a 2.5 nitrogen shock as a secondary spring. The pressure could be adjusted pretty easily. They can be bought in a long enough length to cover the entire range of travel. I am just not sure about the packaging.
Like an ORI strut you mean? I could certainly see that providing additional capacity if you could package it, and it would get you an integrated hydro bump.

Biggest downside would be having to carry a nitrogen tank and regulator if you wanted to adjust. Too bad there are no decent air sprung options like in the MTB world...
 

Buliwyf

Viking with a Hammer
Not sure if air shocks apply well to fullsize trucks. Fine for buggies. I've never seen one small enough for a truck, except for bicycle shocks.

The desert and gravel stuff, is why I'm switching to Sumo's for my next build.
 

Metcalf

Expedition Leader
Like an ORI strut you mean? I could certainly see that providing additional capacity if you could package it, and it would get you an integrated hydro bump.

Biggest downside would be having to carry a nitrogen tank and regulator if you wanted to adjust. Too bad there are no decent air sprung options like in the MTB world...
Yup, Fox and King both make a 2.5" 'air' shock that uses nitrogen pressure ( and is kinda a bad emulsion shock ). I am just thinking that it could work as a secondary spring for load capacity. They have a weight capacity limit of 1200lbs in the 2.5" per unit. That would be 2400lbs of additional payload, not too bad. I just don't think that their is room to package them in addition to the main shock....and the leaf spring....
 

Metcalf

Expedition Leader
Not sure if air shocks apply well to fullsize trucks. Fine for buggies. I've never seen one small enough for a truck, except for bicycle shocks.

The desert and gravel stuff, is why I'm switching to Sumo's for my next build.
Why not? It is basically just an air spring. I would only use it as a secondary spring to help with loads. It wouldn't even need valving inside really. Fox and King both make a 2.5" version that will support 1200lbs per unit. They have 12" travel units which would be about right for the rear suspension.

Honestly, since you don't need internal valving, the shock shaft could be increased in diameter so it just fit in the main body. This would increase load capacity a lot. Make the shaft hollow to decrease the change in spring rate.

The downside would be packaging. I just don't see a place for another large shock to be mounted and be effective without going through the bed.
 

DzlToy

Explorer
Do some research before you purchase from Kelderman.

Twin ORI struts could be an option instead of coils. They act as springs, dampers, bump stops and limit straps, all in one package. A single unit could be used with a light duty leaf to give you the best of both worlds.
 

Adventurous

Explorer
Yup, Fox and King both make a 2.5" 'air' shock that uses nitrogen pressure ( and is kinda a bad emulsion shock ). I am just thinking that it could work as a secondary spring for load capacity. They have a weight capacity limit of 1200lbs in the 2.5" per unit. That would be 2400lbs of additional payload, not too bad. I just don't think that their is room to package them in addition to the main shock....and the leaf spring....
How's about a bell crank? Depending upon the leverage ratio you could tailor the design to the expected load. With multiple sets of mounting holes you could even make adjustments without having to change shock pressure.
 

Recommended books for Overlanding

Metcalf

Expedition Leader
Do some research before you purchase from Kelderman.

Twin ORI struts could be an option instead of coils. They act as springs, dampers, bump stops and limit straps, all in one package. A single unit could be used with a light duty leaf to give you the best of both worlds.
That sounds really expensive! I think an ORI strut is about 800-900 each. I know they promote they are a wonder package. I just don't buy into it really. The dual sided air chamber kinda violates most of what I think works well for spring rate.
 

Metcalf

Expedition Leader
How's about a bell crank? Depending upon the leverage ratio you could tailor the design to the expected load. With multiple sets of mounting holes you could even make adjustments without having to change shock pressure.
A bell-crank or cantilever setup could be interesting. With the air shock concept, it would pretty much need to be a reverse ratio to increase the load capacity, and then that makes packaging really. I do think using something like a 2:1 motion ratio on a conventional bellows bag. That would bring the spring rate down a lot which seems like it could help. It would also increase the travel available to keep from ripping the bag.

The long travel tapered sleeve bag I posted a bit ago seems like a pretty simple solution if they would hold up. That seems to be the big question with bags....
 

enroh

New member
I'd be inclined to go to:
64" Chevy leaf spring pack in the rear with only a few long leaves and and a half length anti-wrap leaf (full length of front of leaf but ends 50mm behind axle housing)
Long travel airbag from BOSS or Firestone or similiar, setup with an automatic levelling switch.
Twin IRONMAN Foam Cell Pro #45094LFE3 13.5" travel shocks on both corners.( 860mm Open 516mm Closed 45mm piston fully rebuildable and adjustable valving with a 3mm thick body)

This is a good compromise between wheel travel, suspension dynamics and the all important load carrying capacity in my opinion.

Being an aussie Id also ditch the "bed" and fit a "Tray" preferrably Aluminium- much more versatile in my personal opinion. May be even fit a tipping tray...
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Peter_n_Margaret

Adventurer
What is the best overall performing suspension on a full-size truck you have done? What would you do different? How good it be?

When I see a wheel off the ground it is a sure sign that the suspension has not done the job required of it.
Leaf springs need to be LONG to have better travel.
Cheers,
Peter
OKA196 motorhome
 

DzlToy

Explorer
Peter will be quite familiar with these, but I must laugh at the 79 Series trucks set up for touring with thousands of dollars spent on suspension, yet they carry a wheel over the smallest wombat hole.

I realise that some 70 series are coil sprung and IMO, that makes it even worse. Spend the money to get an awesome suspension and it will pay dividends in many ways. I also find it strange that no one seems to use stacked transfer cases or ultra-low gearing in t-cases there. I must have watched a hundred hours of very well built Patrols and 70 Series touring or "over landing" just bouncing and banging all over the place because they could not go slow enough for the terrain they were crossing.

Couple this with a poor or mediocre suspension and you risk damaging your truck, the trail and having a white knuckle ride along the way, none of which are necessary.

A popular Toyota HiLux or mini truck upgrade is called RUF/63. This translates to Rears Up Front (OEM rear springs go to the front of the truck, nothing else changes), then a 63" Chevy spring is installed on the rear axle. The ride and flex, with some decent shocks, is drastically improved over the factory setup. Proper articulation allows your tires to stay on the ground, improves control and reduces stress on you and the truck. Flex is not for show or for "rock crawlers", it is the smart way to go off roading, IMO.

Getting proper springs ordered and dampers dialed is a bit of an art, so I am not sure there is a kit or a system that will be the perfect plug and play for your rig. It may seem silly to spend so much time getting components dialed in, but once you have ridden in or driven a rig that performs spectacularly off road, your mind will be changed.
 

luthj

Engineer In Residence
From what I hear, a common problem with aftermarket kits for lifting coil spring 4x4s, is that they are just too high a rate to get the lift. As opposed to a longer spring, which often requires some extra work to install or preload. Since most don't actually go wheeling, the extra firmness keeps the body roll down with their 600lb RTT...
 

enroh

New member
Peter will be quite familiar with these, but I must laugh at the 79 Series trucks set up for touring with thousands of dollars spent on suspension, yet they carry a wheel over the smallest wombat hole.

I realise that some 70 series are coil sprung and IMO, that makes it even worse. Spend the money to get an awesome suspension and it will pay dividends in many ways. I also find it strange that no one seems to use stacked transfer cases or ultra-low gearing in t-cases there. I must have watched a hundred hours of very well built Patrols and 70 Series touring or "over landing" just bouncing and banging all over the place because they could not go slow enough for the terrain they were crossing.

Couple this with a poor or mediocre suspension and you risk damaging your truck, the trail and having a white knuckle ride along the way, none of which are necessary.

A popular Toyota HiLux or mini truck upgrade is called RUF/63. This translates to Rears Up Front (OEM rear springs go to the front of the truck, nothing else changes), then a 63" Chevy spring is installed on the rear axle. The ride and flex, with some decent shocks, is drastically improved over the factory setup. Proper articulation allows your tires to stay on the ground, improves control and reduces stress on you and the truck. Flex is not for show or for "rock crawlers", it is the smart way to go off roading, IMO.

Getting proper springs ordered and dampers dialed is a bit of an art, so I am not sure there is a kit or a system that will be the perfect plug and play for your rig. It may seem silly to spend so much time getting components dialed in, but once you have ridden in or driven a rig that performs spectacularly off road, your mind will be changed.
Actually youll find transfer case gearing and multiple transfer cases are quite common in Aus
 
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