GMC SIERRA 2020 Owner's Manual page 412

Warning (Continued)
jack or placing an object under
the vehicle. See Power Assist
Steps 0 34.
Front Position 1500 Models
Front Position All Other Models
4. If the flat tire is on the front of
the vehicle, position the jack
under the bracket attached to
the vehicle's frame, behind the
flat tire, as shown.
Vehicle Care
Rear Position 1500 Models
5. If the flat tire is on the rear,
position the jack under the rear
axle about 5 cm (2 in) inboard
of the shock absorber bracket.
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