1997 GMC Suburban Owner's Manual - Page 98

Shifting from 4HI to 2HI Press and release the 2HI switch. Thiscan be done at any speed, and the system will unlock automatically. Shifting from4LO to 4HI or 2HI Shifting from 2HI or 4HI to 4LO To shift from 2HI or 4HI to 4L0, the vehicle must be stopped or moving less than 3 mph (4.8 k m h ) with the transmission in NEUTRAL (N). The preferred method for shifting into 4LO is to have your vehicle moving 1 to 2 mph ( 1.6 to 3.2km/h). Press and release the 4LO switch. You must wait for the 4LO indicator light to stop flashing and remain illuminated before shifting your transmission into gear. If the 4LO switch is pressed when your vehicle is in b *ear 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 d h ) and the transmission is in NEUTRAL (N). To shift from 4LO to 4HI or 2H1, your vehicle must be stopped or moving less than 3 mph (4.8 km/h) with the transmission in NEUTRAL (N). The preferred method for shifting out of 4LO is to have your vehicle moving 1 to 2 mph (1.6 to 3.2 kmh). Press and release the 4HI switch. You must wait for the 4HI indicator light to stop flashing and remain illuminated before shifting your transmission into gear. If the 4HI switch is pressed when your vehicle is in gear and/or moving, the 4HI indicator light will flash for 30 seconds but will not complete the shift unless the vehicle is moving slower than 3 mph (4.8 kmh) and the transmission is in NEUTRAL (N). 2-24