Regular oil

In Europe the Prius stipulated oil change period is 10,000 miles using 0w20 synthetic oil.

I believe in the US they suggest 10,000 miles too. You do not want to use cheap oil as the tolerances in the Prius engine are tight.

 

Why would you do that ?

Why not just use what's recommended for an extra ten bucks or so ?

But .... In answer to your question .... NOTHING would happen.

REV

 

"What would happen if I use regular oil for say 5000 miles and then switch back to 0w20?"

Likely nothing but when you mix synthetic with conventional oil residual, or visa versa, there is a chance things will sludge up. Blends as sold to the public have modifiers or such to prevent this, but my opinion on blends is less than conventional oil.

 

There isn't a conventional 0w20 oil. I won't say nothing will happen. As a minimum, I predict your fuel mileage will go down.

So what's the deal? Do you have some old oil on your garage shelf that you don't want to waste?

 

How often do you check your oil?
How long have you kept your last 3-4 cars?
If the truthful answer to the first question is less than about every other tank then it's not going to matter what kind of oil you use.
It's much more important that you maintain the proper volume of oil than it is to worry about one change with dino oil over the first 150,000 miles....or 15 changes with the designer stuff.
If you're going to be keeping the car for less than about 150,000 miles then I wouldn't worry about it either.
Me?
I wouldn't do it for the simple reason that you had to ask about it, which means that it raises a level of concern, but I have other uses for dino oil than Prius longevity experiments.

The answer to your question in real world terms is nothing would happen that you're going to notice, IMHO.

Good Luck!

 

Believe it or not ... Some stealerships offer Prii budget oil changes using 5/30 Dino, at 5k intervals, and fools buy it ... So they have to get 2 oil changes in 10k miles instead of 1 .... Duh ...

REV

 

I would stay with the 0W20 synthetic mainly because of the engine starts and stops.

 

What grade is this "regular oil"?

 

I'm guessing that cheap n nasty stuff you'd think twice about putting in your lawn mower.

 

I would strictly use the oil that is recommended in your owner's manual, 0W20 synthetic. Then drive it for 10,000 miles.