For gas engine center rear of oil pan, it is a cast aluminum pan 15mm bolt and the oil filter is next to and up. When you remove the bolt oil will flow out 12+ inches back.
Bottom of the engine on the oil pan.
Below the oil pan. If you do not know you should not touch it.
It is in the oil pan and that is bolted on the bottom of the engine. Just look around the bottom of the oil pan and you will see a bolt in it. And that will be it.
Where is oil drain plug on 2007 avalanche
Oil drain plug is just to the right side of the oil pan from the filter. Heads up, it is pointed sideways so when the plug is removed oil squirts waaaaay out there. Good luck catching all of it.
on the oil pan
The original engine oil drain plug wrench size should be 15mm.
Look at the rear or side of the oil pan
Lower Side or bottom of oil pan
Bottom of engine on the oil pan.
counter-clockwise
its 9/16's