who is doing extended oil change intervals in prius?

Yeah, never is a pretty long interval, for the Prius transaxle fluid change. I'm with you there. FWIW, Toyota's now recommending brake fluid change, every third year, as evidenced by the 2014 Prius documentation.

But the Honda policy on oil filter interval doesn't seem that extreme, nothing like the Toyota transaxle fluid debacle. More a measured decision, with some benefits.

Agree to disagree?

 

That's one more example of how humans have an incredible tendency to deny any evidence that counters long-held pet beliefs and superstitions.

 

I don't extend my Prius oil changes past 10K, but I do like the 0W30 idea and run that in mine due to my long-held pet beliefs and superstitions as an ex-race car engine builder. I also use full synthetic.

I have driven a couple of work vehicles that used oil and did not have oil/filter changes for extended periods (40K to 50K between changes). However, oil level was checked frequently and topped off every 3 to 4 days as needed. These were relatively high mileage vehicles to begin with and no problems developed, or worsened, due to the apparent lack of frequent oil changes.

Based on my own mythological beliefs, and void of any scientific or evidence based data whatsoever, I wouldn't be afraid to go 12K or even 15K miles between changes but then I would want to put in fresh oil and install a new filter.

I've always enjoyed changing my own oil, brakes, rotors, plugs, tire rotations, axle seals, etc... because it's just my nature to get out in the shop and roll around under a car.

 

Yes...I agree to disagree with you "on this one". It makes no sense to run new clean oil through an old dirty disposable filter to maintain a vehicle/equipment that costs tens of thousands of dollars.

 

I have a John Deere tractor that specifies engine oil changes every 100 operating hours and oil filter changes every 200 operating hours. I think this is a holdover from when oil filters cost $5.00 and oil was $0.30 per quart. Today, synthetic oil costs about $6.00 per quart, but you can still buy an OEM Prius oil filter from the Toyota dealer for $5.00. I have to agree with Frodoz. It makes no financial or technical sense to not change the oil filter at every oil change.

 

It's your car friendly_jack...but you wouldn't make it though apprenticeship in my field.

 

...and when the filter clogs dirty oil bypasses the filter and/or pressure blows a hole in the filter media. The results of that are not simple.

 

While a filter might work "better" after a fashion, due to it being less pourous, it's also impeding flow. You might get some leeway in an oil filter where the oil is under pressure, but in air filters, you are slowly choking the motor. At some point you are doing the same to your oil and risking the bypass engaging.

 

So Honda's engineers are smoking rope, and/or pawns of advertising department?

There is another conclusion, possibly: they tested filter duration, found they were fine for a longer interval?

 

Now, why would Honda bother investigating relevant facts, when they could just follow along with the conventional wisdom of "we've always done it this way, and the sky will fall if we change"?

Nobody has yet explained why using a filter through multiple oil changes is a bit more likely to result in disastrous clogging than is shrinking the filters (and thus the surface area of filter media inside), which car manufacturers have been doing more or less continuously for decades.

 

Exactly. I've done the same "not easy" dissection with spin-on filters from three different (much older) cars, with the same results.

 

Vehicle maintenance is just a conspiracy to take our money based on antiquated principles. I say just remove the filter and never change the oil. With today's superior synthetic oils and technologically advanced engines just add as required. By the time the burn rate gets to say one quart every 1000- 2000 miles it's about the same as a full oil change...and besides the catalytic converter would be due for change by then. This way we all save work, money, oil, waste, air pollution and fuel (if everyone was as smart as us and bought a Prius). Then we just wisely recycle the car about the same time we were going to take on another car payment anyway. If everyone followed these simple practices, we could quickly reverse the damage already done to this earth, and have more time and money to boot. It all makes perfect sense.

Sarcasm.

 

C'mon: one company (apparently) did some research, decided to stretch the oil filter change interval. Not a lot. This means war?

 

Bullets: Even the best of friends and spouses do not and will not agree on everything. How one chooses to maintain their vehicle/s IS their business. ANY forum thread dealing with engine oil quite often becomes as polar as discussing politics.

Now having said that, should you choose "not to" properly take care of your car will it blow up right away?...no...but it's going to have issues and live a shorter life. If you smoke 2 packs cigarettes and drink a 12 pack of beer every day will you die right away?...no...but your going to have issues and live a shorter life. Does saying this amount to war?...no...in fact some might call it passing on a solid coming from a Mechanic or Doctor. Do and believe what want.

Not sarcasm.

 

"Issues" like my last car, on which I normally replaced the oil filter at every third oil change (i.e., about every 16-20K miles)? I retired it last fall with about 606K miles showing on the odometer. The engine never showed any evidence of wear of any oily metal surface, or any sort of failure from filter clogging. Original honing marks were still visible on the cylinder walls when exposed (due to unrelated problems) at around 500K miles. Dissection of numerous used filters from that car revealed few visible particles, consisting mainly of small flakes of carbon(?), never enough of anything to come near clogging the filter. I'm not imaginative enough to understand how the car could've enjoyed a longer "life cycle" if I had "properly" replaced the oil filter every time.

 

So...in conclusion, if we only change the filter every third time, all our cars (not just one isolated Mazda with no real history to reference) will make it 606,000 miles before meeting an unrelated death. I must amend post #55. Bye-Bye.