1994 GMC Suburban Owner's Manual - Page 268

Used oil can be a real threat to the environment. you change your ownoil, If be sure to drain all free-flowingoil from the filter before disposal. Don't ever dispose of oil by putting it in the trash, pouring it on the ground, into sewers, or intostreams or bodiesof water. Instead, recycle itby taking it to a place that collects used oil. If you havea problem properly disposing of your used oil, ask your dealer, a service station ora local recycling centerfor help. Engine Oil (Diesel Engines) It's a good idea to check your engine oil level every time you get fuel. In order toget an accurate reading, the oil must be warm and the vehicle must be on level ground. Turn off the engine and give the oil afew minutes to drain back into theoil pan. If you don't, the oil dipstick might not show the actual level. To Check Engine Oil Pull out the dipstick and clean it with a paper towel or a cloth,then push it back in all the way. Remove it again, keeping the tip lower. 6-22