GMC Sierra 3500HD 2001 Owner's Manual page 87

Mirrors
Inside Day/Night Rearview Mirror
Push the tab under the mirror rearward to reduce glare
from headlamps behind you after dark. Pull the tab
forward for normal daytime operation.
Outside Manual Adjust Mirrors
Adjust your outside mirrors so you can see a little of the
side of your vehicle and have a clear view of any objects
behind you. Some mirrors can be folded in, to enter
narrow doorways.
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The use of hood mounted air deflectors and add
convex mirror attachments may adversely affect
mirror performance.
2-38
Camper-Type Outside Mirrors
(If Equipped)
If your vehicle is equipped with the camper
mirrors, they can be adjusted so that you can have a
clear view of any objects that may be behind you.
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on
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type