That depends solely on how much you intend to spend on the car. The two most preferred based on sales would be either Castrol, or Mobiil 1. You can get other oils like Royal purple, redline, or even AMSoil, but those tend to be a bit more expensive and harder to find. If it were my car, i would run a standard conventional oil (castrol GTX), and make sure its changed every 3 mo/3000 miles. Period.
Your "operators manuel" should explain which type of oil to use. I have a 96 Buick, LaSabre, that uses 10/30 wt.
3387A
I Use Chicken Oil!
refrigerant oil has to do with A/C and is is R134A bit motor oil is 5w30 all year
10 30
around 5
The oil filter location for the 2000 Buick LeSabre is on the front of the motor. Look just to the left of the fan belt near the left side of the motor.
Oil level sensor is on side of oil pan.
4.5 quarts with new oil filter
10w30 says it right on the oil cap.
it should be in a bag on the back seat.... If not check at your local parts store
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