What's the best way to deal with rust on VW Caddy III side sills? Is it better to repair small sections or replace them completely?
It depends on how deep the rust is. Minor spots can be repaired, but if corrosion has spread, replacement is usually the safer and longer-lasting option.
I ran into the same problem with my VW Caddy III and initially tried small repairs, but the rust kept coming back. Eventually, I decided to replace the side sills completely. While researching, I found repair side sills for VW Caddy III 2004–2011 https://kyivparts.com/remchastini/arka-zadnia-prava-mitsubishi-outlander-i-03-07-polcar at KyivParts online store , which seemed like a practical option in terms of fit and price. It might help to compare similar parts before making your final choice.