Chevrolet 2008 Uplander Owner's Manual page 73

CAUTION:
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Using the vehicle's built-in child restraint as a
booster seat for a larger child could cause
injury to the child in a sudden stop or crash.
A child whose weight is over 40 lbs (18 kg),
whose height is over 40 in (1 016 mm) or
whose shoulders are above the shoulder belt
slots for the harness system should use a
restraint system that is appropriate for their
size, either an add-on booster seat or the
vehicle's safety belt. See Child Restraint
Systems on page 1-49 or Older Children
on page 1-42.
Securing a Child in the Built-In Child
Restraint
1. Raise the head restraint until the lower edge of the
head restraint is even with the top of the seatback.
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