i have a 1999 Pontiac Grand Prix SE with the 3100 motor that has 137xxx miles on it and it calls for 10W-30 but the place that did the oil change put in 5W-30 oil in it. will this effect the car in any bad way?
Don't worry about it as it will not hurt anything. The 30 number is more important the the number before the "w".
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