Skim vs. Fat Free

Dear Car Talk

Dear Car Talk | Oct 01, 1990

Dear Tom and Ray:

I have a 1984 Pontiac Grand Prix. The gas gauge says "unleaded gas only." Would it be wrong to use "lead free" gas? If yes, what is the difference between unleaded and lead free?

TOM: I used to have the same problem with milk, Josephine. My wife would send me out to the supermarket to get fat free milk. She said it was healthier for me. Well, all I saw on the shelf was skim milk--I didn't see any fat free milk! So I did what any normal person would have done. I bought a gallon of Ben and Jerry's Coffee Heath Bar Crunch ice cream instead and told her they were out of milk.

RAY: Actually, Josephine, the point my brother is trying--unsuccessfully--to make, is that sometimes, two names are used for the same exact thing. There is absolutely no difference between skim milk and fat-free milk. It's like hot dogs and frankfurters.

TOM: Unleaded gas and lead free gas are ALSO two different names for the same thing. There is no lead in either one. And they're both fine for your car.

RAY: And besides, Josephine, you don't have to worry about making a mistake, because the gas pump wont let you. The only filling station nozzles that will fit into your car are unleaded nozzles. They were designed that way to prevent you from adding the wrong kind of fuel accidentally and ruining your catalytic converter.

TOM: So if you're ever not sure, just try filling up the tank. If the gas goes in, it's unleaded. If it pours all over your shoes, try another pump.

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