This is listed in your owner's manual, and somtimes on the oil fill cap. Call a dealer to make sure. 5W-30. It is listed in the owner's manual. The 3.8L V-6 uses 10W-30. Make sure you use the 5W-30 to allow for closer tolerances on the 3.4L, especially in colder weather. I would run 5w30 until you hit about 50,000 miles then switch to 10w30 as wear becomes more prevelent.
in the oil pan
80W90 gear oil.
Drain the oil from your 2000 Chevy Impala oil pan. Remove the oil pan retaining bolts. Remove the old oil pan gasket and clean the surface. Put the new oil pan gasket on and reverse the process.
front of engine neat oil filter
It is on the very bottom of the engine on the oil pan.
Only in the corners.
Read Your Owners Manuel
Use Castrol GTX.
The recommended oil type for a 2000 Chevrolet Impala is 10 W 30. The car uses automatic transmission fluid that can be purchased at any auto parts store.
4 1/2 to 5 quarts of oil depending on engine size and oil filter capacity.
Probably every 5000 miles. Or 6 months.