GMC SIERRA 1994 Manual page 240

Changing the Tire
Start with the jack, the
jack handle and the
ratchet.
If the flat tire is on the rear of the vehicle, you'll need the jack handle
extensions also.
I
Attach the jack handle
(and jack handle
extensions, if needed)
to the jack.
With the UP marking
on the ratchet facing
you, rotate the ratchet
to the right.
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