First OCI - 156k miles Prius

[Greg L]

Bought a used 2010 Prius with 1.8 engine. Car had 151k miles when we bought it. Not sure what dealer fill was.


Did my first OCI this past weekend, at 156k miles and used the following:

2 quarts Pennzoil 0w40
2.5 quarts Pennzoil High Mileage 0w20.

Engine calls for 0w20 (at 4.8 quarts). Manual says that 5w30 can be used, but not on a regular basis.

Question: was I ok in adding the 0w40 weight?


I figured things were safe, being it is summer....and the temps this week are 80 to 95 where I live.


GL

 

[Brybo86]

Thread title makes it sound like the oil hasn't been changed in 156k

 

[maverickfhs]

Phew, good

 

[maxdustington]

Originally Posted By: Brybo86
Thread title makes it sound like the oil hasn't been changed in 156k

That's why I came.

 

[Audios]

Why do they say you cant use a 5w30 for multiple changes?

 

[Greg L]

Manual said you can use it, but go back to a 0w20 on the next oil change.

 

[JC1]

Originally Posted By: Brybo86
Thread title makes it sound like the oil hasn't been changed in 156k


The beauty of the English language. Keeps lawyers employed and spouses disagreeing.

 

[Charlie2015]

"Question: was I ok in adding the 0w40 weight?"

Yes. If you car does not burn oil, use only 0w20, though, so you can get the best fuel economy.

 

[oil_film_movies]

Originally Posted By: Greg L
Question: was I ok in adding the 0w40 weight? I figured things were safe, being it is summer....and the temps this week are 80 to 95 where I live.
You could do that year-around, not just summer. Really, you can go a little higher in viscosity without causing any wear issues. Fuel economy will take about a 1% hit due to the thicker stuff. Not a whole lot of MPG loss!

When I say you can go a little thicker with no wear issues, a good rule of thumb is don't go over about 40% KV100 thicker. So, a 0w20 has a KV100=8.5, then don't exceed about KV100=11.9. Check the Widman visc mixing calculator at https://www.widman.biz/English/Calculators/Mixtures.html , and you get KV100=10.2 for our mix, probably a 0w30 which is fine.

Toyota is required to strongly recommend 0w20 in the U.S. due to EPA CAFE requirements. The rest of the planet probably regularly uses xw30 or xw40 in that engine.

I just tell people never go thinner than the what the Owner's Manual says, as that's when wear problems can happen.

 

[Greg L]

Great, thanks for the response (sorry for da konfusion to everyone else)