Walked in Pepboys without my glasses and accidentally bought the Castrol High Mileage 5w-20. I did not realize until I was filling in the used bucket of dirty oil back into the quarts. What should I do now? Should I change the oil again or am I good? Will there be a drop in performance or gas mileage? It's driving me crazy how I didn't notice I bought the wrong oil for my baby

 

It might not lubricate enough, like people use super low weight oils to flush their engines because when you get up to high RPM it won't lubricate fast enough and that cause problems.

I am not sure about 20W though, its quite close to 30 but I am having mixed feelings. I think its okay for a few days or weeks but once you start to shred that oil it'll drop down into the 18s and 17s then it would be bad.

 

Thanks for the quick reply. So as long as I drive under 4rpm I am good to go? I drove the car to and from work and it felt the same.

 

It's factory fill for lots of cars now.
Just drive the car.

 

Recommend you change it. 20 weight is not recommended by Nissan and it might not provide the film strength needed to prevent metal to metal contact (wear) within your engine when it gets hot and/or under stress. While other manufacturers are indeed recommending 20-weight oils, the engines they recommend it for have very close tolerances and are designed to run on that viscosity oil.

 

Thanks for your input talkinghorse. Will definitely change the oil again once this weekend comes.

 

I honestly woundnt worry about it, as long as u are not driving a 3.5 with oil consumption issues then u should be fine.

 

Haha I came up with a good analogy for oil!

Lets say that you are washing your hands and what do you use? Water right? Since its really low weight (Maybe 0W?) It cleans good. But if you use something like cooking oil to clean your hands the oil will stick to your hands because its heavier.

In engines, that only thing I can think of is when you rub your hands together really fast to warm your cold hands or whatever and if you were going to use lubricant something really low in weight like water, then all of it is going to splash off, but if you use something like grease it'll lube your hand no matter how fast you go.

Sorry completely unrelated but I wanted to share hahahah

 

Water is heavier than oil.

 

^^^

Alright I guess I will keep the oil until my next oil change. Although I do feel uneasy about the lighter vs heavier oil thing.

 

drive it for 6000km then dump it...
forget about the blah blah blah... VQ is bulletproof

 

If it was my car, I would change it. Like talkinghorse said, the car is not meant to run on that oil. I would gladly spend the $15 or whatever is costs to replace the oil than to take the chance of damaging the engine.

If you want to justify changing the oil so soon, you could consider it as an oil flush

 

I'd dump it and just take it as a lesson learned.

 

I wouldn't dump it. It isn't THAT thin, and it is getting colder outside...which is better for thinner oil. There are people that swear by 0w-20 in cars just like the Max.