2002 GMC Sonoma Owner's Manual - Page 100

NEUTRAL: Use this position when you start or idle your engine. REVERSE (R): To back up, press the clutch pedal. After the vehicle stops, shift into REVERSE (R). For vehicles equipped with the VORTEC 4300 V6 engine, you must wait six seconds before shifting into REVERSE (R). Slowly let up on the clutch pedal as you press the accelerator pedal. Shift Light If you have a manual transmission, you have a SHIFT light. NOTICE: Shift to REVERSE (R) only after your vehicle is stopped. Shifting to REVERSE (R) while your vehicle is moving could damage your transmission. Use REVERSE (R), along with the parking brake, for parking your vehicle. This light will show you when to shift to the next higher gear for best fuel economy. When this light comes on, you can shift to the next higher gear if weather, road and traffic conditions let you. For the best fuel economy, accelerate slowly and shift when the light comes on. While you accelerate, it is normal for the light to go on and off if you quickly change the position of the accelerator. Ignore the SHIFT light when you downshift. 2-30