I know it is just a matter of time ultimately but I am keen to know what preventative measures people are taking in their RR's (I'm thinking L322's here). Do people underseal? Is there anything that can be done to protect the wheel arches and door sills beyond this?

Waxoyl or dinatrol is your best bet, needs to be prepared first by removing all loose dirt and rust then sprayed on ideally. Done properly, IE in cavities and behind plastic trims it does work and will extend the life of the car

Unless the rust is deep and structural which will require a lot of effort you are probably best just giving it regular jet washes to remove dirt holding moisture from the usual places and keeping it outside to allow air drying or in a heated garage to dry it off. Worse place is an unheated garage. 2012 TDV8 Vogue (L322)

I do the complete underside and inside the sills and box section with Lanoguard every year.

Sills and wheel arches are in fantastic shape.

Jim

I sprayed inside tailgate with dinatrol also removed all wheel liners and cleaned all of the rubbish out before fitting rubber edging

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