GMC 2003 Sierra - Manual (Page 303)

The front bumper lower 3 ¡r dam is held in place by a
series of push'pins located ground the lower edge oí the
front bumper. The push-pins are accessible from
undem&ath the front bumper^ The following steps must
be pertomed on each of the push-pfns to remove
the air damr
1. Insert a tool into the
push-pin slot and pull
downward until the
push-pin snaps loose.
E. While ccriiiinuing to pull
downward on the
push-pin, squeeze and
turn the eKpandabiB
end Df the push-pin
with a tool until it
releasas from the
retainer.
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