Consider too, it Prius wants to be known for being “green,” that might also include extended oil changes…the motor is working much less with a maintenance free electric motor, so it seems very reasonable.
I Run Mobil-1 Extended Performance, Exclusively, But I Change It At 5,000 Mile Intervals Just Because It Makes Me Feel Good.
The manufacturer of my car recommends full synthetic oil for operation in my temperature-extreme climate. Conventional oil and synthetic are not equal in performance. Synthetic is superior for cold start lubrication and for its anti-sludging qualities.
CSA
The worst part about 10,000 mile oil changes is the majority of owner’s will not check their oil level over that year/10k. Most Prius’s will be okay however cars do burn some oil and not all of it will be there after 10k miles. This will make the oil stressed.
Bad idea IMHO for majority of car owners. Or is the sump huge on the car with something like 8 qts?
I would have an extremely difficult time letting my engine go 10k between changes regardless of what the manufacturer recommends. I’m not saying they’re wrong, but it would bother me personally too much not to change it earlier.
Sometimes it appears car makers go a bit too far in order to advertise their cars as virtually maintenance free. My girlfriend’s 07 Uplander manual states to change the trans. fluid at 100k. That sounds insane to me. Also, Pontiac G8’s have lifetime transmission fluid. I remember reading in a car magazine that you couldn’t change the fluid on that car even if you wanted to.
Again, I’m not saying this is the case with your Prius, after all, you already bought the car and at this point they’re not trying to sell you anything based on maintenance longevity, but I still couldn’t do it.
Great point Andrew. Aside from myself and by brother, ZERO people I know check their oil, ever. Sad and potentially expensive.
So, theoretically if it gets 30 % better fuel mileage than a simlar non-hybrid car, you could lengthen the oil change interval by 30%. But not 100%!!!
That’s where the new formula (or like spec’d oil) probably comes in. They’ve had more than enough “time in country” to assess usage profiles and any lubrication related issues under real conditions. It took Ford quite a few years to extend the 5w-20 recommendation from 5k to (iirc) 7k.
People would be surprised at how long they can keep their oil in use. Unfortunately, GM patented the Oil Life Monitor …and no one else wanted to pony up. Ford came very close with it’s idle hour meter on its taxi and police units. The rest are sophomoric in comparison. Even the Euro’s with their oil “sensors” add another part to go bad.
Most people, in practice, are going to service their car in even increments during the year. It usually breaks down to 2, 3, or 4 oil changes. This is especially true in 4 season climates. They don’t like to “carry over” these events where one oil change will fall in one year …and two the next. Some may go by strictly mileage, but that often upsets their “rhythm” with all the other synchronous events in their lives.
I don’t think too many owners will make the 10k mark unless it also means one year.
Was that directed at me, Caddyman? If so, I’m not sure what you are disagreeing with. I said that unless extra additives to control acid formation are used, all oils will drop pH. That will create a soup that will eventually start to dissolve your engine. Exxon-Mobil guarantees their Extended Performance oil for extended mileage, but also sells synthetic oils for 7500 or fewer miles between changes.
If the prius gets 30% better mileage than the Corolla, the oil change interval should be 1.3x5000 miles=6500 miles.
The other argument made was that the Prius engine operates over a more beneficial power range wih less steep accelration and deceleration. That may add another 10%, bringing it to 7150 miles.The synthetic oil cannot make up for the difference, unless it is the Mobil 1 or European spec long drain interval, as use in Vokswagens and BMW. The Prius engine is basically the same as the one in the Yaris.
The main reason, however, as one poster pointed out, is that the Prius is sold as a GREEN car and should also have long drain intervals. It’s basically a MARKETING decision, not one from the engineering department.
After all this, I still would not recommend the 10,000 mile drain interval, unless you plan to sell the car in 4 years or less. I would go 6000 max for the longest engine life and use 0W30 synthetic.
I have a relative who does not even know how to open the hood of his car. And he was trained as an engineer! He relies on the garage to check his fluids.
My recommendation is as follows:
If the OP is the type of car owner who trades/sells his car after 3, 4, or 5 years, the 10k interval is probably not going to cause any problems for him. As to the next owner(s) of the car, all bets are off regarding the ultimate lifespan of the engine before severe oil burning sets in.
If the OP is likely to keep the car for more than 5 years, I think that the added cost of one or perhaps two extra oil changes per year is good insurance against excessive engine wear and sludging. As mountainbike has said in the past, oil is relatively cheap, and engines are expensive. In this case, the synthetic oil is a bit pricey, but it is still a lot cheaper than a new engine at…maybe…110k miles.
The synthetic oil cannot make up for the difference, unless it is the Mobil 1 or European spec long drain interval, as use in Vokswagens and BMW.
Unless the oil carries the OEM spec.
Mobil 1 only sells ONE EXTENDED DRAIN OIL. That’s the EP line. Not ONE other oil, including the 0w-40 is recommended for extended drains.
Now before cock back and hammer me, read the recommendations from M1’s site yourself. The 0w-40 is Oh-EE-EM recommended for Oh-EE-EM drains that may be quite long in comparison to your engine, but they’re Euro engines that the lubricant was designed around to meet those longer drains. They’re sumps are typically bigger and XOM was in on the design of the engine in cooperation with the builder.
Otherewise, M1 says “follow your owners manual”. The EP line is the only one buffered for the long haul on a non-OEM spec’d interval.
The Toyota 0w-20 is a totally advance lubricant. No product of XOM, that’s available OTC matches it for viscosity index. That is, on the shelf with a M1 label, there are only inferior products and non of them currently meet the spec’s of the Toyota 0w-20.
“This oil allows 10,000 miles drain intervals under normal (easy) coditions.”
Mobil1 Extended Service is guaranteed for up to 15,000 or 1 year change intervals under easy conditions.
How much could it cost to change the oil and filter on this tiny 4 cylinder engine? $30? $40? I would never leave oil in an engine and a filter on an engine for that many miles or that period of time. The extra $50 or so to cut the interval in half would be small change if you ever had to replace this engine. Rocketman
Thanks for the additonal input. I don’t use 0W20 Toyota oil in my Toyota. The bulletin I got in the mail recommended ILSAC GF-4 SAE 5W20 for my 2007 Corolla, and also ILSAC GF-4 SAE 0W20 (presumably synthetic). Neither of these are specific Toyota specs.
It refers to a different bulletin, EG050-04, for Prius lubrication recommendation. The Prius engine is basically a Yaris engine.
It said future Toyota engines will be develped to use these 2 previuosly mentioned lubricants, and the dealers want to start standardizing on these oils.
It also added a note saying:
“DO NOT use these oils in engines other than those listed above (a long list). These low viscosity oils CANNOT maintain lubrication in engines with older designs and could result in smoke emissions from the tailpipe and/or unusual engine noise.”
In other words, don’t use thin oil in older engines, ANY older engines.
The bulletin stressed “fuel economy and better envronmental benefits”, not a word about longer engine life. So the whole thing is driven by fuel economy (CAFE) and allowing the dealers to stock only one or two oils.
So, please tell me where I can get that special “Toyota 0W20 spec” which eludes me in the bulletins received so far.
have a company like blackstone labs test your oil and it will tell you everything you needed to know about oil deposits, and make appropriate recommendations to oil changes. I have a 2006 Avalon and sent my oil to the lab. Toyota recommended 5k miles, they didn’t recommend any fewer miles due to the newness of the engine at the time. They even saw silica in the oil that they say came from the casting of the block, and that it should go down as the engine gets older. I had a Dodge caravan with the 3.3L flexfuel and changed the engine at 3K miles which was on par, but as the engine got older I had to change it more often. The “BEST” answer is to have your oil analyzed, and go from there…for new cars still under warranty then stick to the schedule at the worst end of the change scale. The analysis may recommend additives like copper to aid in lubrication and minimize engine wear.
I don’t understand why people don’t want to change the oil in their vehicles on a recommended basis. Is it a hassle,too costly, or an environmental problem?
The people who recommend that you change oil every 7,500 or 10,000 miles sell cars. The people who recommend you change oil every 3,000 miles sell oil. I like 5,000 mile intervals no matter what kind of oil you use.
I kind of agree with sometimesDIYer. My manual says 7500 miles under ideal conditions. The dealer says i can go that distance, but puts a sticker in the window indicating the next change is at 3,000 miles (using a synthetic blend oil.) I figure 5,000 is probably a good time to do it. A 7500 or 10000 mile interval? I say “Pay me now or pay me later.” At least that’s what my dad used to say (he was a mechanic for well over 40 years.)
I’ve had many people tell me that if I used synthetic oil I could run 10K mile oil change intervals. This is true, but I always wonder how long my engines would last at 10K mile intervals. My daily driver is an '88 Ford Escort with 516K miles on it, still has the original engine and the change interval on it has probably averaged somewhere around 5K miles each (sometimes fewer, sometimes over), but I’ve also always used conventional oil. If I’d used 10K mile intervals would it have lasted for 51 oil changes? It has lasted 103 oil changes at 5K mile intervals. Using conventional oil and a new filter at each oil change doing the oil change myself it costs about $15 per oil change or $1545 over 516K miles, if I used synthetic with a new filter at 10K mile intervals it would cost about $23 per change or $1173 over 516K miles a savings of only $372 in 516K miles. If the engine didn’t last this long with the 10K mile interval it would have cost me way more to replace the engine than the $372 I had saved on oil changes. That engine didn’t even start using any oil until it was between 250-300K miles. To me KNOWING the engine will last is worth the extra expense and time it takes to do an oil change. I also still use 10w40 instead of the lighter weight oils that were recommended for use in this engine and the engines in my other cars.