2010 GMC Savana 2500 Cargo Owner's Manual - Page 291

Checking Coolant The vehicle must be on a level surface when checking the coolant level. Check to see if coolant is visible in the coolant recovery tank. If the coolant inside the coolant recovery tank is boiling, do not do anything else until it cools down. If coolant is visible but the coolant level is not at or above the COLD FILL mark, add a 50/50 mixture of clean, drinkable water and DEX-COOL® coolant at the coolant recovery tank, but be sure the cooling system is cool before this is done. When the engine is cold, the coolant level should be at or above the COLD FILL mark. If it is not, there could be a leak in the cooling system. If the coolant is low, add the coolant or take the vehicle to a dealer/retailer for service. How to Add Coolant to the Recovery Tank for Gasoline Engines If your vehicle has a diesel engine, see "How to Add Coolant to the Coolant Recovery Tank" under "Van Models" in the Cooling System section of the DURAMAX® Diesel Supplement for the proper coolant fill procedure. { WARNING: You can be burned if you spill coolant on hot engine parts. Coolant contains ethylene glycol and it will burn if the engine parts are hot enough. Do not spill coolant on a hot engine. Notice: This vehicle has a specific coolant fill procedure. Failure to follow this procedure could cause the engine to overheat and be severely damaged. If coolant is needed, add the proper DEX-COOL® coolant mixture at the coolant recovery tank. 6-29