has anybody fitted the parabolic springs now available from ATW for Isuzu and Fuso?.....and if so.....do they work well and are you using them together with Robo Shocks or any other brand?
Hi Adrian,
We have only just fitted trial sets to three Isuzu NPS and one Fuso FG and still haven't setup our new machine which will enable us to check the spring rates of each spring pack and then dial them into the weight of each individual truck, so the first ones were a little bit of guess work. We originally guessed the spring rates and nitrogen pressures in the shockabsorbers for the first NPS as being higher than they should have been.........as a result, the ride was too harsh once it hit the corrugations on an outback trip that took the owner down to SA and back mainly off the bitumen.
When I drove that vehicle earlier, it was fantastic on the country roads around here but obviously it was still too hard for bad offroad conditions. I can tell you that even then it was a dream to drive compared to a standard NPS. We got the vehicle back a couple of weeks ago and changed the rear spring pack and dropped the pressures in the shocks but kept the same valving............below are the comments from the owner of the vehicle after changes to the original suspension setup.
"The suspension is a vast improvement on previous. We've just returned from several days at Fraser Island - the truck performed well in the sand and on the inland tracks. The highway ride (and probably gravel road as well?) is much smoother; previously every bump or pothole would be felt regardless of speed. Now the truck runs smoothly across imperfections in the bitumen and the suspension feels much more supple. Went for a very short run through the State forest and the suspension seemed smoother on the corrugations ............................The body moves around but all in a reasonable manner and not uncontrolled"
This vehicle does not have the in-cab ride control that we also offer which allows the driver to alter the shock absorber pressures on the fly and therefore greatly change the handling characteristics of the vehicle .......as an example, when changing from slow and technical offroad driving where articulation should be at a maximum to mid-speed corrugations where a too harsh setup can be damaging or even dangerous when cornering to high speed black top cruising where body roll can be minimized and a setup that is too soft will effect braking. Don't get me wrong, the in-cab control isn't a requirement for this suspension but it is a handy option and does work.
We will only be offering the parabolic suspension as a complete kit........front and rear spring packs, 4 of our shockabsorbers and Aeon style bump stops.............just putting them on the front does not work. Fitting them without correctly valved shockabsorbers does not work either and we don't want any trucks with them getting around that aren't properly setup and giving the wrong impression.
Hey, by the way, I'm not the guy who handles the sales of these. If you do want to know anything about that side of it, just call our office.
Thanks mate. Regards John.
