In Scandinavia, it is common to regularly leave the car at professional rust-proofing firms every 3-4 year. The methods may have different names (Tectyl, Dinitrol, Tuff-Cote), but basically they are quite similar. There is a unique procedure for each make and model, and after steam cleaning and heat fan drying (the whole process takes 3 days) all nooks and crannies are treated with thin, penetrating oil. It is particularly important to get inside rocker panels and the like. First time they'll drill holes for the probes, later they'll just remove the plugs.



The underbody will in addition get a protective layer of thick chip guard.

The program is quite extensive, this is the treatment scheme for the 1974 140 series cars. The numbers refers to a text page describing the how-to's and type of oil and tools to be used.



I highly recommend this treatment. Mine has had it regularly since new in 1987, and even if I drive it on salt treated roads in a coastal climate, there is absolutely no rust on the car. At the yard I see a lot newer cars totally rusted out because of owners' negligence.

Erling.

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