Synthetic oil maintenance

7,500 miles worked well for me with the 2004 using 5W-30 synthetic.

10,000 miles is the recommended for the 2010 with 0W-20 synthetic.

 

If you care to keep the 5 year / 60K mile powertrain warranty in effect then you would do well to observe the 6 month / 5,000 mile change requirement. If you don't care because you believe that an engine failure during the warranty period is unlikely, then 7,500 miles is fine. That is the interval that I personally observe.

 

i have read several posters here talk of 10k miles on synthetic 5w30.
and that is with oil analysis to confirm ol condition is still acceptable.
i plan to go 10k with my oil changes.
i ascribe to this theory as well, the prius even when rolling 10k miles hasnt actually run the engine for the full time, it runs much less than astandard engine, perhaps only 75% of the time?? so oil is worn 25% less also.
keep in mind we are assuming regualr car usage, oil needs to be heated regularly to keep it clean/dry,also keep in mind trips need to be long enogh to properly warm up the engine, which takes at least 10 minutes, longer in cold climates.
infrequent use, or short trips, wont properly heat up the oil, and will shorten its life.
my other car has an oil light that comes on somewhere btw 10k and 15k, based on usage etc, and has always gone about 13k on an oil change, its going on 120k trouble free miles

 

Heating the oil does nothing to keep it clean. But running the engine so the oil temp is past 212 degrees F, long enough to boil off any condensation is a good idea.

 

In cold weather short trips it needs more than warm, long. I guess I am the odd man out because I have EXTENDED my oil changes to 5k with synthetic. I use M1 0w-30. Some get cheap after buying the car, maybe because they will trade it anyway. I don't. I will pay the $30 it costs me to change every 5k, rather than gather oil to send in and spend $30 to test it, to go 10k.

When having the oil changed it is better to bring them a quality oil filter, instead of the bargain brands most shops will use. The Toyota OE Denso, or even better the Toyota TRD made in USA. This is a true premium filter. I still have some Japan Toyota filters left (expensive) but will buy the TRD when I need more. IMHO.

 

indirectly the moisture causes more dirty oil, and faster oil breakdown, i was just too lazy to be precise.
i deal with oil issues in all my watercraft, high performance 4stroke pwc's and a boat.
cars dont usually have so much to worry about with moisture in the oil.
and i dont consider making an educated descision to extend oil changes to a reasonable interval as being cheap.
doing all the work myself, as i have seen the "quality" in service time and time again form private garages and dealerships, maintaining 5 cars and 3 watercraft, why waste the money, and time?
its more of a time issue for me.
doing brakes, tranny's, diffs, wheel bearings, oil changes, all adds up time quick, so no need to overdo it.
you do know toyota now recomends 10k mile oil changes for us prius models, and always did in europe and japan??

 

^^^If using 0W-20 oil^^^

 

None of the things that Lextoy said are specific to 0W-20 oil.

It's true that in countries where 10k miles (or 15k km) oil change intervals are standard that they specify good quality synthetic or at minimum synthetic blend oil. But don't confuse the two issues. Whether or not 0W20 or 5W30 synthetic is more appropriate is purely a question of the climatic conditions under which you'll be driving.

 

The Prius engine has a reputation for solid reliability. I've only seen one story here about an engine gone bad (main bearing), and that was a car where the poster was not the original owner. Maybe the dealership techs that post here occasionally can also comment as to the low rate of Prius engine failures. The fact that they can be sourced at a junkyard for as little as $300 is a good indication that nearly all engines will last the life of the car if minimally maintained. To me it seems simple: conventional oil every 5,000 miles, or synthetic every 10,000 miles. The Toyota filter is a good one, but so is a Supertech from Walmart.

 

I just changed the oil in my FIL's 05 Prius with under 17K miles. Mostly it sits in the garage. I used M1 5W30 and a M1 filter. I will be buying the car from him soon and plan to use M1 0W30. I can see sticking to 5K oci's if you do a lot of city driving because fuel dilution can be significant in a Prius I understand. I will be doing a lot of highway miles with it so I'll try 7500 mile oci's for a while with the plan of going to 10K if things look OK. I'd love to use 0W20 in it but even though the Europeans use it in 05's, I'm trying to locate ANY data that suggests engine longevity might be compromised.