Has anyone seen this before? previously all my spring bushes have been worn out but this time!!!
 

looks like thats been getting some heat from your exaust.

Yep, had it happen to me a few times when I was using Nolathane brand bushes. I think the grease works out of them and then they just eat themselves, especially when you compound the effect with dust. Most new bushes are knurled where they fit over the sleeve to contain the grease. I haven't had the problem since I started using superpro bushes.

This normaly happens when poly/urethane bushes come in contact with some solvents, usually thinners when the car  or suspension parts are painted. Any painting happened near the bushes????A simple overspray will make bushes crumble away into powder.... 
 
Cheers

I dont think they are NOLATHANE brand, they are polyurathane but Nolathane bushes are usually red in colour not blue. I have no direct connection to the brand but just trying to be fair to them when it would appear it is not their product
 
G

No shame on the bushes, the first few years of life was forest hell for them, the last couple have been a breeze on club cruises, It has just never happened to me before, no paint or solvents, no heat as exhaust is miles away and its both spring eyes (shackles are ok). I was thinking along the same lines as Tanz, that perhaps it was an age/drying thing. trouble is the bushes that I replaced then with are the same age (as per the photo) like all good rally teams I carry a full set of spares. I have ordered a set of bushes from smcka to hopefuly sit in the shed for a couple of years.
 
Just had a brain wave!! may be its Zetec power!!!

Heat will do that, especially if the crush tube is not wide enough and the body is rubbing on the bush.

Been there, done that...
 
Drivers side:

 
Passengers side:

 
Cheers

It's called hysteresis, it happens when the urethane starts to get hot. It cooks from the inside out. I see worse cases of it due to using a lot of urethane parts in mining pumps.

Did the car have bad axle tramp?

It's either that or incorrect installation.