Welcome to VWwA otzi
One of the popular LCV mags, Delivery mag has a Caddy as a long term runabout.
Anyway as they did country driving they decided to have sound deadening installed in the Caddy via rubber or carpets (can't remember which one sorry).
I think carpet and rubber would be the go.
I would also ask the dealer as they may have a clue via previous customers
Good Luck with your future purchase whatever it may be.
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