1997 GMC Sonoma Owner's Manual - Page 74

4LO: This setting also engages your front axle to give you extra traction. You may never need 4LO. It sends the maximum power to all four wheels. You might choose 4LO if you were driving off-road in sand, mud, deep snow and climbing ordescending steep hills. Indicator lights in the switches showyou which setting you are in. The indicator lights will come on briefly when you turn on the ignition and one will stay on. If the lights do not come on, you should take your vehiclein for service. An indicator light will flash while shifting. It will remain illuminated when the shiftis completed. transmission. The preferred method for shifting into 4LO is to have your vehicle moving 1 to 2 mph (1.6 to 3.2 km/h). Press and release the 4LO switch. You must wait for the 4LO indicator light to stopflashing and remain illuminated before shifting your transmission into gear or releasing the clutch pedal. If the 4LO switch is pressed when your vehicle is in gear and/or moving, the 4LO indicator light will flash for 30 seconds and not complete the shift unless your vehicle is moving slower than 3 mph (4.8 k m h ) and the transmission is in NEUTRAL (N) or the clutch pedal is engaged. On automatic transmission equipped vehicles, if your transfer case does not shift into 4L0, your transmission indicator switch may require adjustment. With your transmission in NEUTRAL (N), press and release the 4LO switch. While the 4LO indicator light is flashing, shift your transmission into PARK (P). Wait until the 4LO indicator light stays on before shifting your transmission into gear. This will get you into 4L0, but you should take your vehicle in for service to restore normal operation. Shifting from2HI to 4HI Press and release the 4HI switch, This be done at can any speed, and the front axle will lock automatically. Shifting from 4HI to 2HI Press and release the 2HI switch. Thiscan be done at any speed, and the front axle will unlock automatically. Shifting from 2HI or 4HI to 4LO To shift from 2HT or 4HI to 4L0, the vehicle must be stopped or moving less than 3 mph (4.8 km/h) with the in transmission in NEUTRAL (N) vehicles equipped with an automatic transmission. The clutch pedal must be engaged on vehicles equipped with a manual 2-26