Xantia rear sill/arch corrosion info

[wurlycorner]

I've read a few odd posts on here about rust on the rear sill/arch seam corroding on Xantia's, but not found full coherent info on it (maybe just me).

After seeing the latest pics on a FS thread, these are the clearest I've seen of what can happen - George, I hope you don't mind me using your pics! Tell me if you do and I'll remove, of course)




These are from the same reg/model/mileage as mine, but Mine has NO signs of corrosion. Clearly I want it to stay that way...

What causes the corrosion at this particular location and why are some cars susceptible to it and some not?

Ideally pics to help explain this please, putting all the info together in one useful thread!

Thanks

[RichardW]

Er, the sticky just above your head explains all....

http://www.frenchcarforum.co.uk/forum/v ... =3&t=42540" onclick="window.open(this.href);return false;

[wurlycorner]

So mine is an early car and has a sunroof, so should have this problem. I'm guess I'm just lucky mine hasn't started to corroded yet then (probably helped by not having been on the road for the last 5 years so although it's the same age/mileage as the silver one I posted above, it's had a lot less years of salt/spray etc. crap thrown into the arch!

[citroenxm]

No no.. its appears to be more cars WITHOUT sunroofs that go.

My exclusive is sound all around the back and cills. Yet a T plate spares car without a sunroof is bad.

ive got an Sx mk.1 with sunroof and thats also rather good too last time I looked. But I got rid of a v6 without sunroof and it was bad..