Salt invades little nooks and crannies

Dear Car Talk

Dear Car Talk | Nov 01, 1990

Dear Tom and Ray:

Living in a snowy town, I've always wondered about the wisdom of washing my car in the winter. Somehow it seems to me that spraying the salt off my car might do more harm than good by allowing the salt to invade little nooks and crannies and causing an acceleration of the rusting process. What do you think?

RAY: Mechanics and doctors don't agree on much, Nettie. But they do agree on one thing; salt is nasty stuff. Doctors don't like it because it contributes to hypertension, and mechanics hate it because turns perfectly good cars into junk.

TOM: The only reason municipalities use salt on the roads is that it's cheap. Rather than pay the snowplow drivers double overtime and a half to plow the roads all night, they dump truck-loads of salt out there, and the snow melts as soon as it hits the ground.

RAY: And it's another classic application of the famous Click and Clack axiom: It's the Stingy Person that Spends the Most. We may be saving a few bucks on snow plowing now, but look what salt is doing in the long run. It's seeping into our groundwater supplies. It's eating away at our roads and bridges. It's turning cars into jalopies even faster than my brother can!

TOM: So the short term answer to your question is that you SHOULD wash the salt off your car. In fact, if you have a chance you might also hose down a bridge or two! Seriously, any damage salt will do in the nooks and crannies of your car is insignificant compared to the damage it does to the rest of the car's sheet metal and under body.

RAY: And the long term answer is to start a campaign to stop your town or county from using salt on the roads. Write a letter and tell them how you feel. There are environmentally safe alternatives to salt, like spreading cinders or sand, or even good old fashioned snow plowing.

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