Kogzbilt Revisited

Hi All,
Just a quik update, a few things happening on the Kogzbilt front,
Have dragged arse out to garage, first time in 12 months or so owing to common health issues which we can all relate to.
Thought I could have talked either son into taking on Kogzbilt, but neither showed onterest or enthusiasm. so gonna pace meself and just do the odd hour out there when able to
Have had plenty of time to ruminate on what I may like to achieve, came up with brainwave of pulling existing rear axle/suspension out replacing same with a new tandem axle trailer suspension I had bought for another project.
Preliminary measurements say we can move the front drive axle forward 8 inches and still have plenty of drive line left, beef the rear hanger up around the chassis taper and still get the rocker assembly in WITHOUT cutting the chassis. Have another spare running chassis we can butcher to make a trailing lazy axle.
Bit of ingenuity required, but is feasible.
Will take photos shortly of existing rear axle/suspension as is and also new tandem axle layed out on concrete.
This tandem trailer axle is a bit light, 3000/4000lb, but can be beefed up with HD hangers, shacle plates , rockers etc all readily available, can be beefed up to 5000kg!
Can cut & shut spare drive axle to make the lazy trailing axle, setting rocker angles to get the right weight distribution, but my technical advisor says can be nutted out with narrower rocker beam.
Thats it! Had about three goes to post this missive, see how this goes.
Cheers, Dave64

Sounds like it will fill in the time between smoko and lunch. What are you going to do after this?

Looking forward to progress photos and details.

Lang

Been having a bit of a look on Youtube re setting up these centre rockers.
As they are designed for trailer use, they all seem to be setting them up so they are load sharing,i.e. 50/50 by adjusting the HEIGHT or the centre rocker.
You can buy several different styles of standard as well as HD rockers which can give that vertical movement anything from zero to 4 inch travel, so I'm thinking that THAT'S what will determine the load sharing ratio??
It may be a bit of trial and error, I'm thinking that a split of 60/40 or maybe even 70/30 in favour of the leading drive axle over the trailing lazy axle.
Don't quite know how I'll achieve that ratio as the front hanger will be moved forward 8 inches, the rear hanger stays where it is,
Both spring eyes get put back in original line, and new rocker hanger goes roughly in the centre of both.
I also see that when a lot of these tandem setups are retrofitted, both front and rear are fitted in such a way that the very front and very rear spring eye is bolted directly to the shackle mount, not using the supplied shackle plate extensions.
Wonder why??
Some blokes have set a camera up to record just how much travel there is in that centre rocker, from zero movement to up to 4 inches.
They also ALL replace the most forward and most rear nylon shackle bushes with bronze type bushings, as the "plastic" ones chop out in no time, but even the heavy duty greasable bronze bushings need regular servicing.
By lining up the original spring eyes to the repositioned spring hangers and using HD shackle plates etc, there is also a sliding cross brace available to stop suspension walking "sideways", also after market shock absorber plates as well.
Just depends how far you would want to go with it!
Get the basic tandem suspension in first, get it so the load sharing sorted,
always come back later and install HD components.
Realise that may be unusual amount of wear in the front or the forward shackle pivot points, but only way to find out is try it!
Dave64

Hey, Lang!
Had been doing a bit of scratching around between smoko and lunch.
May not have posted it last time, but have a shortened alloy tray bought off a bloke at a clearance sale, put heavy frame under it, has to have rear tailgate folded up, going to make a tipping flat top out of it, have all the valving, ram, etc, only 18 inch removable sides reckon that once I mark it up as to where I want it to sit on the chassis, will pull it off and finish it, chuck a coat of paint at it.
Was originally mounted on 3"X3" hardwood runners, they go back on.
Looking forward to seeing what it looks like with tray on bogie set up!
This thing is highly unlikely to be carting anything heavier than maybe a bit of gravel or roadbase,
But dont want it to ride like a billy-cart, want a bit of give in the suspension.
Otherwise will think I'm back driving F or R model Macks with camel- backs!
Will take progressive photos.
Cheers, Dave64

This all very exciting, maybe chuck some air bags in the drive axle spring area and you could then just dial up the weight transfer as require
I reckon 70/30 would be the go for weight distribution

Good to see your getting back into things


Paul

Hi Mrs!
Did cross my mind about the air bags, bro in law had a set fitted to his cab/chassis Land cruiser with tipping tray, cost him about $600 to fit them. maybe worthwhile looking somewhere down track.
Lots of things to do before I get that far, though.
I chucked a set of air shockers under my Prado when having the HD suspension fitted. Bit of a PITA though, gotta keep constantly checking the pressure on them at the servo.
Maybe a bloke could engineer some sort of air compressor/air tank set up, but getting complicated enough for now.
Dave64

       

 

ARB have a little 12v compressor set-up for vehicles fitted with air lockers. With that system you could raise and lower pressure on the go to get the perfect match for load and road conditions.

One of those little $20 Super Cheap 12v compressors could easily be plumbed into an old tank (reckon an LPG gas bottle would be OK) or just hook it direct to the airbags.

Got a nice “free” compressor with set of tyres bought 6 years back. Keep a lookout for deals.