Hello, I live in florida and recently did an oil change
to my car. Will it have any negative side effects
that I used mobile 1 5w-30 instead of what the
manual called for which is mobile 1 0w-40.
As you are in a warmer climate and this time of year it doesn't get really hot so you should be alright through the winter months but return to what it calls for come spring or when the daytime temps start creeping up. There should be a chart in the owners manual that shows the ideal temp range for the most common oil viscosity used in your engine.
Just use the correct type of oil next time.
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