How often to change synthetic oil?

Warranty requires oil change every 5K, regardless if it is synthetic or not. After your warranty is up, that's a tossup.

 

Are we getting 3 free oil change from the dealer?? I will be getting my new Prius also. I will ask when I get mine.

 

I didn't get any free anything except the first tank of gas.

 

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Keep receipts of materials. You are correct, it couldn't be proven the work was or was not actually done at 5K intervals, but keep a log of odometer reading when you do the changes, and keep receipts of the oil, filters and gaskets.

 

I only got one free oil change for both of ours. I never thought to ask for 5 free oil changes. I suppose they could have only said no.

I would change the oil every 5K. I have oil analysis kits (to send to Blackguard or Blackstone cannot remember the name). I orginally got them for my F250 but since it was stolen I will analyze the Prius oil. I was told we may need to change the oil not because of excessive dirt but due to sheering which will lower the rating. I will check.

I am not sure about switching to synthetic since I doubt I will keep the car 20 yrs. In 10 yrs we may need to get the upgraded Prius that gets 250 mpg. Although if it does increase the MPG and runs more quiet I may switch. I have 2K miles to think about it.

 

<div class='quotetop'>QUOTE(DanMan32\";p=\"89926)</div>

Dan:

Absolutely correct for North America. For some odd reason, Toyota appears to have lowered across the board the oil change interval. My 1990 4Runner had a 12 month, 7,500 mile for "normal" use, 3 month 3,000 mile for "severe" use.

Interesting how the Prius in Europe has a 12 month 16,000km (10,000mi) oil change interval.

It doesn't matter what brand synthetic oil you use. If you extend the oil change interval and should happen to experience a rare engine problem during warranty, that would be all Toyota needs to tell you "TFB pal you're SOL."

After warranty, if you still have the car, then I would see no problem with 12 months or 10,000 miles. There are two different oil filters, get the tall one. On all my cars and trucks, once off warranty I did 12 month oil changes, 6 month oil filter changes, no matter how many miles. No problems with synthetics.

It's unclear if this motor is as prone to sludging as the 3.0 V6 (Sienna, Camry) that created a lot of press. If you operate in a severe winter climate like where I live, then EVERY motor will produce sludge if run on conventional oil.

Also, a conventional 5W-30 will only work reliably down to about -22 F. Any colder, especially -40, and the oil is solid as a brick. So there is cold temp flow characteristics to consider, which I don't think you have to worry about.

In my winter city driving conditions, especially at -40, it's prudent to run a synthetic oil with a lot more detergents and dispersants. As an example: Mobil 1 0W-30, Amsoil (HDD 5W-30, XLF 5W-30, ASL 5W-30, TSO 0W-30), Esso XD-3 0W-30, etc.

The oils listed above will reliably control the condensation resulting from low temp conditions when the motor doesn't get hot enough to boil off the condensation. They will prevent the formation of any sludge and varnish.

Otherwise, since we're stuck with 6 month 5,000mi oil changes, the cheap stuff should be ok. Unless it turns out these motors also have a sludge problem.

I'm not sure if you can expect huge MPG increases. The European oil testing authority, ACEA (Association des Constructeurs
Européens d'Automobilies), compared a reference Heavy Duty 15W-40 to xW-30 and xW-20 oils.

On average, an xW-30 (Eg 5W-30) increased fuel economy 2%, and an xW-20 increased fuel economy 2.5%. If you're expecting something like 10%, that's probably wishful thinking or a fantasy.

Note: the CVT already uses a synthetic oil, Type WS.

Jay