2010 GMC Sierra 1500 Crew Cab Owner's Manual - Page 16

Manual Lumbar If equipped, this control is located on the outboard side of the seat. Power Lumbar Increase or decrease lumbar support by turning the knob forward or rearward. If equipped, this control is located on the outboard side of the seat. On vehicles with two-way lumbar, press and hold the top of the control to increase lumbar support. To decrease, press and hold the bottom of the control. On vehicles with four-way lumbar, press and hold the front of the control to increase lumbar support. To decrease, press and hold the rear of the control. To raise the height of the support, press and hold the top of the control. To lower, press and hold the bottom of the control. See Power Lumbar on page 2‑7. 1-10