Torsion Bars - Old or New?

[GTVeloce]

Can someone tell me - do torsion bars lose their spring over time/with use like springs do? i.e. I'm looking at 27mm bars and wondering whether it would be fine to buy second hand or should I go new.

Thanks
Julian

[Duk]

Theoretically they would suffer fatigue and start to sag with use (not so much age) in the same way a coil spring starts to sag, but the more metal there is to make the 'spring' then the more durable it will be.

[minipete]

I've had my Giulietta for 25 years and 170,000kms.  The suspension hasn't been touched and it still sits at the same height as when I got it. 

My 1974 Renault 16 has torsion bars and has done 320,000kms without sag.

I would have no hesitation in using second hand bars.

Pete

[alfa duk]

 This is providing that you can get second hand, not that easy to find bars larger than standard.

[Duk]

^^^^ Hmmmmmmmmmmm scary