2004 Hummer H2 Owner's Manual - Page 266

Driving in Water Heavy rain can mean flash flooding, and flood waters demand extreme caution. Find out how deep the water is before you drive through it. If it is deep enough to cover your wheel hubs, axles or exhaust pipe, do not try it - you probably will not get through. Also, water that deep can damage your axle and other vehicle parts. Your vehicle is capable of depths up to 20 inches. Know how to judge whether the water is deeper than this before proceeding into it. If the water is not too deep, drive slowly through it. At faster speeds, water splashes on your ignition system and your vehicle can stall. Stalling can also occur if you get your tailpipe under water. And, as long as your tailpipe is under water, you will never be able to start your engine. When you go through water, remember that when your brakes get wet, it may take you longer to stop. {CAUTION: Driving through rushing water can be dangerous. Deep water can sweep your vehicle downstream and you and your passengers could drown. If it is only shallow water, it can still wash away the ground from under your tires, and you could lose traction and roll the vehicle over. Do not drive through rushing water. See Driving in Rain and on Wet Roads on page 4-43 for more information on driving through water. 4-40