Thread: 110 SUSPENSION UPGRADE?

Originally Posted by gasman

Just back from our first o/n trip with boat in tow.
Average performance, but exceptional mileage considering I went through Newcastle from Swansea end and got every red light. 12.9 ltrs/100 weighing in at 2700kgs + the boat, so not bad, just very slow hence all the red lights.
Suspension is doing its job, but on the expressway, you have to plan ahead as any sudden changes in direction upsets everything and will induce a roll over……...

Take a gander at your trailing arm bushes (particularly the chassis end) they can wear quite quickly and dramatically effect handling at speed (tail end gets 'swervy').

I recently replaced mine and the improvement in stability during direction changes is marked.

Originally Posted by gasman

Just back from our first o/n trip with boat in tow.
Average performance, but exceptional mileage considering I went through Newcastle from Swansea end and got every red light. 12.9 ltrs/100 weighing in at 2700kgs + the boat, so not bad, just very slow hence all the red lights.
Suspension is doing its job, but on the expressway, you have to plan ahead as any sudden changes in direction upsets everything and will induce a roll over……...

Setup on my county is not unlike yours in terms of springs etc.
Dobinsons C51-015 fronts and C51-011 rears (400lb/in). Firestone airbags in the rear. About a 40mm lift from standard I think, rooftop tent, weighing around 3T fully loaded/fueled etc.
Its stable towing our 1.5T Jayco with light weight distribution hitch.

Two things I particularly noticed while getting mine to this stage:
- When I removed my rear sway bar to fit my long range tank it made a HUGE difference to body roll. That was with rear springs around the 320lb/in rating. Heavier rear springs improved body roll, and a bit more air in the bags (20psi) when loaded up also helps.
- Prior to having my swivels slotted it was quite (nasty) twitchy on direction changes at speed. No issue now.

Although you are a similar weight to mine, you've got some rear overhang that I don't. Apart from suspension bushes already mentioned, I'd be looking at getting it on a weighbridge (with and without the boat) and getting some axle weights. Picking you could be quite light on the front with combination of boat and rear overhang.
Get the caster measured too, as if its zero or negative that definitely makes them twitchy.\

EDIT: Just had another look at your photo's and you've actually got bugger all more than a wagon in terms of rear overhang. Still be interesting to get axle weights - I've got an Isuzu holding the front of mine down

Steve

"Prior to having my swivels slotted it was quite (nasty) twitchy on direction changes at speed. No issue now".

What is a slotted swivel. Some kind of nasty STD? No seriously, what is that?

Originally Posted by gasman

"Prior to having my swivels slotted it was quite (nasty) twitchy on direction changes at speed. No issue now".

What is a slotted swivel. Some kind of nasty STD? No seriously, what is that?

In a nutshell its a method of adjusting caster to get it back to factory settings.

From the factory, they come with approx 3deg positive caster in the front suspension, but that reduces as you lift the ride height. Caster reduces approx 1deg for every half an inch IIRC.
A couple of inches lift and you're down towards 0deg. Positive caster gives you directional stability and predictable steering. None or negative makes them twitchy when you change direction.

With them being live axle, the 2 main ways to increase caster are to either fit caster correction bushes (which also changes diff pinion angles which can create other issues), or to slot the mounting holes on the swivel ball where it bolts to the axle housing. Once slotted, the swivels can be rotated (rearwards at the top) to increase caster and get it back to the factory 3deg.

Steve

Re axle weights, my Puma runs at GVM and I weigh bridged her the other day - 1.2T front, 1.9T rear axle.

Set up is tubular winch bar plus wire rope Warn, forward mounted RTT, full expedition roof rack with awnings, long rang tank, cargo drawers, water tank behind rear seats and in rear guards right distribution matches axle load limits perfectly!

FWIW, I found caster was more of an issue with twitchinless/directional stability (I went with caster corrected radius arms) rather than sway/roll over terror

How do I know if the bushes are buggered on the trailing arms.
Mine sit a little off the face where they connect, but seem OK??????
And considering my load, would I be better going for poly or OME.

Thanks