I'll check when I get home if it's shown in ePer what changes were made to the suspension on newer models.
Apart from some changes to the design of the wishbone, all Stilos have the same front suspension design.
As far as I know, the only change to the spring was that the painting process was improved to help prevent corrosion from salt water. However, if you, or a garage, use the hook on type spring compressors, they are likely to cause damage to the paint. You can see on your photograph above that the spring has broken next to a corroded part of the coil.
Broken springs posted on the forum have always been broken at the bottom. The Fiat spring compressor tool is designed to compress the spring while it's fitted on the shock absorber, so that the hooks only go over the top of the spring.
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