GMC 1999 Sierra 1500 Pickup Owner's Manual page 215

Slow down, especially on higher speed roads. Your headlights can light
In remote areas, watch for animals.
If you're tired, pull off the road in a safe place and rest.
up only so much road ahead.
Night Vision
No one can see as well at night as in the daytime. But as we get older
these differences increase. A 50-year-old driver may require at least twice as
much light to see the same thing at night as a 20-year-old.
What you do in the daytime can also affect your night vision. For example, if
you spend the day in bright sunshine you are wise to wear sunglasses. Your
eyes will have less trouble adjusting to night.
But if you're driving, don't wear sunglasses at night. They may cut down on
glare from headlights, but they also make a lot of things invisible that should
remain visible-such as parked cars, obstacles, pedestrians, or even trains
blocking railway crossings. You may want to put on your sunglasses after you
have pulled into a brightly-lighted service or refreshment area. Eyes shielded
from that glare may adjust more quickly to darkness back on the road. But
be sure to remove your sunglasses before you leave the service area.
You can be temporarily blinded by approaching lights. It can take a second or
two, or even several seconds, for your eyes to readjust to the dark. When
you are faced with severe glare (as from a driver who doesn't lower the high
beams, or a vehicle with misaimed headlights), slow down a little. Avoid
staring directly into the approaching lights. If there is a line of opposing
traffic, make occasional glances over the line of headlights to make certain
that one of the vehicles isn't starting to move into your lane. Once you are
past the bright lights, give your eyes time to readjust before resuming speed.
High Beams
If the vehicle approaching you has its high beams on, signal by flicking yours
to high and then back to low beam. This is the usual signal to lower the
headlight beams. If the other driver still doesn't lower the beams, resist the
temptation to put your high beams on. This only makes two half-blinded
drivers.
On a freeway, use your high beams only in remote areas where you won't
impair approaching drivers. In some places, like cities, using high beams is
illegal.
When you follow another vehicle on a freeway or highway, use low beams.
True, most vehicles now have day-night mirrors that enable the driver to
reduce glare. But outside mirrors are not of this type and high beams from
behind can bother the driver ahead.
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