After you have 80K miles on a car do you still need to use the same weight oil?

Question

Like since the engine is probably a little looser, doesnt it make sense to move from 5w30 to 10w30?

Answer 1

You can use the same oil weight it wont hurt the car any

Answer 2

If you haven't abused the engine, you should be able to stay with the manufacturers recommended oil.

Answer 3

The people who designed and built your car don't think so.  I have never seen a recommendation from any vehicle manufacturer to switch to a heavier weight of oil after any number of miles, nor have I seen any independent evidence that would support such a thing.

I have plenty of customers with 200k + miles that are still using 5W30 and several with 300k + that do the same.

Answer 4

If you kept your oil changed all the time when it was due.....you may not have as much wear as you think.

You might want to use the oil for higher mileage engines. The formula is different...it's made to soften seals and gaskets to keep them from leaking

Answer 5

If it was me, i would leave it just the way it is ,if the engine is running good and not causing you ant problem why would you wony to change anything,but if you find the need to change it from a 5w to a 10w wieght oil then do it , it's not going  to hurt the engine .

Answer 6

I agree with you completely. I heard, and believe, 5w30 is not an ideal wt. for most new cars. As was explained to me, the manufacturer's recommend the 5w30 to enable the car to get very slightly better fuel economy because the lighter oil allows the engine to turn a bit more freely.  This boosts their fleet average and is a good sales tactic. The engine will last till the guarantee is no longer in effect but probably would be a slightly less worn engine had a higher viscosity oil been used.