Oil....

Pretty much not. The Prius engine should get less wear than any other. Dinosaur oil every 5,000 miles works perfectly well. Nevertheless I do use Mobil 1 in mine, thinking (perhaps mistakenly) that it minimizes my consumption of petroleum products.

Note that the engine actually needs only three US quarts at an oil-and-filter-change, not 3.9 quarts.

 

I've always used Amsoil (synthetic). I'ts made a difference in MPG in other cars I've owned, but I haven't noticed any change with it in the Prius.

 

Please, please, please.....I went through hell trying to figure out how much 3.9 quarts was (is?). And I actually figured it out. Then, if I recall, everyone here said to just put in 3.5, which is EASY to figure out.

Now you are saying 3.0??

 

FYI Synthetic would, in theory, allow you to drive beyond the 5,000 mile interval without the same level of concern of oil viscosity break-down guaranteed to occur with dino (regular) oil.

Here's the thing... the Toyota parts counter guy told me that the warranty becomes an issue if you're not changing every 5,000 miles regardless so save the money and change regularly. Synthetic, even synth-blend is spendy. That's my two cents. That's what I do with my wifes 2007 which already has about 42,000 miles on it.

However, with my 2004 which has over 130,000 miles in it I go FULL synthetic (not a blend) and a high-end Bosch filter and change it every 10,000 - 15,000 miles and you know that it gets just as good as hers on gas mileage and except for a more wheel bearing noise it drives just as good as hers!

 

3 quarts is too low I think, just stick to 3.5.
Or, put in 3 quarts let the oil settle, check dipstick, add more as needed.

 

I'm not trying to be mean,

but don't we have enough answers to this oil question, simply found by using the forum's search feature?

I think the oil horse has been beaten to death until it is nothing more than a matted hair rug.

ZC1

 

That's exactly what I've been doing for four years' worth of oil changes. Every time, after adding three quarts the oil level is halfway between ADD and FULL on the dipstick. That is perfectly fine so there is no need to add more. I've never seen the oil level change noticeably between oil changes.

This works because the *dry capacity* of the system is 3.9 quarts as stated in Toyota literature. After draining the old oil about a half quart remains inside the engine coating inner surfaces and in the sump. You'd die of old age before all of that would drain out.

 

Everybody needs a hobby-horse :_>

 

I use synthetic oil in everything from my 7 year old Tundra, (since new), to the lawn mower. I will be using it in my new Prius. I use Royal Purple, which I think is the best, and superior to Mobil 1. Buy it on the internet, it's a lot cheaper there. Your engine will run smoother, cooler and less friction, thus better gas mileage. Go to their website for their rundown tests.