1996 GMC Sonoma Owner's Manual - Page 71

Electronic Transfer Case(Option) If your four-wheel-drive vehicle has the electronic transfer case,the transfer case switches areabove the radio controls. 4LO: This setting also engages your front axleto 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 show you 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 vehicle in for service. An indicator light will flash while shifting. It will remain illuminated when the shift is completed. Shifting from 2HI to 4HI Use these switches toshift into and out of four-wheel drive. You can choose among three driving settings: Press and release the 4HI switch. Thiscan be done at any speed, and the front axle will lock automatically. 2HI: This setting is for driving in most street and highway situations. Your front axle is not engaged in two-wheel drive. 4HI: This setting engages your front axle to help drive your vehicle. Use 4HI when you need extra traction, such as on snowy or icy roads, or in most off-road situations. Shifting from 4HI to 2HI Press and release the 2HI switch. This can be done at any speed, and the front axle will unlock automatically. Shifting from 2HI or 4HI to4LO To shift from 2HI or 4HI to 4L0, the vehicle must be stopped or moving less than 3 mph (4.8 km/h) with the transmission in NEUTRAL (N) in vehicles equipped with an automatic transmission. The clutch pedal must be engaged on vehicles equipped with a manual 3 32