yeah I knew I might get onto trouble! But I'm not sledging Nutto, just pointing out that from what Nutto has said it is more than likely NOT the damper's fault that it has failed (as he has implied).
Nutto, as you kind-of already know IFS torsion bar fronts have limited scope for ride height lift but I am surpised you have had dramas with a measured 30mm of lift.
When modifying suspension, we must ensure both bumpstops are doing the bumpstoppering (that is, limiting the suspension stroke top and bottom) rather than the damper although with standard spec dampers you can usually get away with ride height increases as long as the suspension architecture remains standard. This must be checked at installation to ensure 'one size fits all' dampers are working within the correct stroke/range.
But as you said, the damper was being stressed before you bumpstops came into play. Every sudden change in road surface (such as apothole) allows the torsion bar (or spring) to almost instantly ram the suspenion to full droop. It's either the bumpstop or damper that limits/stops this motion... and dampers aren't designed for it. Dampers can often be killed in minutes suffering these conditions.
As for just one dying - often the left-hand front shock dies before the Right. With road camber etc you will more than likely find the car will be leaning a little to the left; this may only be 10-15mm but this is sometimes enough to 'protect' the right-side damper. There are also more potholes etc due to cracked road edges on the left side of the road. Also, most utes carry the fuel tank and battery on the LHS and even with suspension 'jacking' to get the vehicle level on flat ground, there is more weight, therefore more movement, on the left.
So why yours died.. dunno! 
HTH.. and what did you do to fix? Is there slightly longer damper you can install, without causing problems the 'other' way (by limiting 'bump' or compression travel)?
Geetee
What you say is correct, and covers what factors i was explaining that likley lead to the failure, however, will clarify & summarise a few things:
- As mentioned eariler, the shock that failed was the
right hand (drivers) side, not left hand, so although it makes sense that the left cops a bit more due to camber, edges etc, it didn't ring true in this case.. I guess it must have been a few bad 'hits' on the RHS
- As the factory shock is the same length as the bilstein, it also has the same issue of taking the 'hit' before the bump stop can save it. It appears this situation becomes an issue from the showroom floor ONLY when torsion bar is wound up, due to reduced downward travel, however, it is poor form that it sold like this
- I could look for a shock with a length so as to let the bump stop do it's job, however, I would have the situation where I would hit the bump stop when It could be avoided by the next point...
- I feel a better solution may be to ease the torsion bars down 15mm so that I can effectively gain back some downward suspension travel. This would result in the shock operating more toward the 'centre' and less likely to top out. I would still also get a slightly longer shock that lets the bump stop hit first, it's just that when sitting a tad lower in the front, i'm also less likey to hit the btm bumpstop. Also better for CV's - reduces horiz angle
- IF i'm worried about loosing frontbody height, I can legally step up from 245/70/16 tyre to 255/70/16 tyre (yes I can, do the maths....
) to get some back (7mm to be exact, half the 14mm increase in rolling OD))
- Yes i said the billie failed, however, any shock would in this situation, and as I have put the originals back in until I rectify the geometry, (which, in hindsight appears not right from the factory anyway) I expect that they may suffer the same fate
- I still think it was a harsh call on the poor understanding, as I thought I pretty well covered what you said!!
When I get a chance to change them over, I'll get some pics with the wheel off and hub hangin, to see exactly what the gap is to the bump stop, and then source a shock with length to match. I'll then get the local truck wheel aligner here to adjust the bars down 15mm and reset the camber.
nutto
