2002 GMC Envoy Owner's Manual - Page 265

Whatever the condition -- smooth ice, packed, blowing or loose snow -- drive with caution. If you have traction assist, keep the system on. It will improve your ability to accelerate when driving on a slippery road. But you can turn the traction system off if you ever need to. You should turn the system off if your vehicle ever gets stuck in sand, mud, ice or snow. See "Rocking Your Vehicle" in the Index. Even though your vehicle has a traction system, you'll want to slow down and adjust your driving to the road conditions. See "Traction Assist System" in the Index. If you don't have a traction system, accelerate gently. Try not to break the gentle traction. If you accelerate too fast, the drive wheels will spin and polish the surface under the tires even more. What's the worst time for this? "Wet ice." Very cold snow or ice can be slick and hard to drive on. But wet ice can be even more trouble because it may offer the least traction of all. You can get wet ice when it's about freezing (32_F; 0_C) and freezing rain begins to fall. Try to avoid driving on wet ice until salt and sand crews can get there. 4-41