Broken ATW parabolic leaf

[Marko1960]

Hello All,
We are part way into our shake down trip for recently completed motorhome...details of vehicle contained in thread " Nearing the end".
Basically a 2012 FGB71 ex mine bus....ATW with Singles and parabolics. En route from Coffs Harbour to Townsville, we noticed when on sealed roads with dips the truck would bounce quite a lot, taking a while to settle again. Average speeds 80 kph. Assumed shocks were responsible. Truck has only done 31000 km. Took truck to weigh bridge this morning, these are the figures obtained:
Front: 2500 kg (2800 allowable)
Rear: 2960 kg (5760 allowable)
Total:5460 kg (6500 gvm)
While inspecting shocks, it was notice the distance between bump stops and diff averaged 10mm. Is this normal?
Passenger side rear uppermost leaf (the one with the locating eye?) is recently broken approx 100mm back from front. No traces of rust at break and no marks indicating any form of impact.

Questions
- Is the distance between the bumpstops and differential ok/normal for these leaf packs?
- Do these leaf packs need to re-set/replaced?
- Does anyone know of a preferred repair agent for ATW in Townsville?
- Does anyone know if ATW can supply single leaves?

cheers

Mark

 

[SkiFreak]

Have you called ATW?
Normally they are quite responsive regarding the equipment they sell.

 

[Marko1960]

That's my intention Monday morning.....only discovered the problem today, but thought I'd sound out the community first.

 

[Aussie Iron]

Hello All,

Passenger side rear uppermost leaf (the one with the locating eye?) is recently broken approx 100mm back from front. No traces of rust at break and no marks indicating any form of impact.


Mark

Not unheard of. Mines replace a few and some have even been converted back to standard springs.

Dan.

 

[stephenh1235]

Hi to all responders on this post, I would like to ask so I can gain some understanding & learn, = the photos 4th & 7th showing bumpstop to diff housing clearance, there appears to be a lot of available thread on the u-bolts I guess due to the minimal number of spring leafs compared to standard? I note the spacer between the springs and the diff housing & wonder if this was added to with either a larger block or spacers it would provide greater gap bumpstops to diff? Thanks, Steve

 

[Marko1960]

Hello Steve,
Upon reflection and further research, I now believe that the bumpstop clearance is not a problem as I previously stated. It seems that they may be a Timbren or Timbren style of bumpstop, designed to have minimal clearance and act as part of the suspension system, providing an additional "springing effect".
As such, I've sent a query to ATW as to the availability of the affected leaf in the pack, and believe that the others are OK.
Cheers, Mark

 

[gait]

ATW recently shipped a rear spring pack for FG649 to Newman (WA) for me. Main leaf broke about 100mm from rear hanger. Easier whole spring than a single leaf. U-bolts were provided, I asked for bushes to be included.

Any reasonable workshop can replace a spring in a couple of hours.

Dave (ATW stores) very helpful. Quicker to phone, spring can be on its way same day.

My front bumpstops are timbren style (from ATW with kit). Rear bumpstops are original with additional spacer (springs raised vehicle about 70mm).

Check with Dave about u-bolts. He has several lengths for different setups. I recall sawing a bit off the ends when I fitted my springs, but its a long time ago.

Also, if no override leaves, the short thin plate above the main leaf on rear spring may need a bit chopped off the ends (without marking the main leaf - take care).

I recently changed shock absorbers to Koni (softer bounce, harsher rebound) which removed some residual "thumping".

 

[Marko1960]

I ordered spring pack, shocks and u bolts from ATW yesterday. Dave & Jon very helpful.

 

[gait]

PS springs break ..... doesn't matter if parabolic or original, if its karma has run out it will break ....... an original spring can even break a leaf on a German autobahn. .......