Chevrolet 1993 S-10 Pickup Owner's Manual page 68

Features & Controls
How long should you keep the block heater plugged in? The answer depends
on the weather, the kind of oil you have, and some other things. Instead of
trying to list everything here, we ask that you contact a General Motors
dealer in the area where you'll be parking your vehicle. The dealer can give
you the best advice for that particular area.
Automatic Ilansmission
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