I have a 02 grand am. This is my first time doing the oil change on this car. I just found out that the person that was doing it was using 10w40. I looked in the cars manual and it says 5w30. Would the 10w40 hurt the car. Should i still use the 10w40 or change it back to 5w30? New 2 this stuff so thanks for the help.
Grand am Oil Q's
- Thread starter BigRob
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10W40 wont hurt the car. If you are in a part of the country that is warm all year round, florida, southern calif., etc. you can use the 10W40 but if not the 5w30 will be better for cold/warm weather with regard to gas mileage.
09G6GT
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I agree with melsg5, 5w30 - 5 is the viscosity or thickness of the oil when its cold or when the engine is cold, when it heats up the viscosity or thickness of the oil is 30. Same with the 10w40 - 10 thickness when cold, 40 thickness when warm. So if your in the cold I would go with 5w30 even if you have close to freezing temps in winter. If your in a place where its warm all the time, I would go with 10w40. All depends on preference.