2013 Prius 10k Factory Fill

[CATERHAM]

Originally Posted By: Apollo14
How do we know the starting viscosity was 8.5?

Do we have a VOA of the factory fill?

Yes a very good point.
It's more than possible that the FF is a 0W-16.
Certain Japanese made Honda models have been coming with what was referred to as a 0W-10 (before the formalization of the 0W-16 grade) for years.

 

[CATERHAM]

Originally Posted By: mikefxu
Originally Posted By: CATERHAM
So you topped up with some Castrol at some point?
I would recommend you go with TGMO 0W-20 as the replacement fill. For the money there simply isn't a better engine lube for your Prius.

Yes. It will get what ever branded 0w-20 that is on sale. Will do UOA in 50k intervals.

That's fine, but just so you know the OEM 0W-20s
are unique. They are at least 25% lighter on start-up even at room temperature and have higher AW additive levels.
If the price is an issue, since TGMO is also supplied in bulk you can usually negotiate a pretty good discount from the service/parts dept on getting a couple of empty oil jugs filled.

 

[Shannow]

Originally Posted By: CATERHAM
Originally Posted By: Apollo14
How do we know the starting viscosity was 8.5?

Do we have a VOA of the factory fill?

Yes a very good point.
It's more than possible that the FF is a 0W-16.


I'm tending to agree...previous Prius FF UOAs were in the 7.2-7.4 range, but with very reduced flashpoints, or fuel dilution nudging 1%.

 

[mikefxu]

Originally Posted By: hljmesa
How did you get the lab report to paste in your comment ?

I wish to post a report but cannot figure out how to do it?

Can you tell me how ?

I took a screenshot of the PDF, uploaded it to the image host, and then you can post image.