Maybe I am totally misguided, but to me it is not clear that it is essential to change today's high quality synthetic oil every 12 months on the dot, even if the ICE has gotten very little use in that time. That does not mean that I would wait 10 years, but if it ends up being 15 months, I cannot see how that would be harmful to the vehicle. Am I wrong in concluding this?
I ran my engine, on purpose, a bit more often in the first 6 months of owning my prime last year. Based on gas usage, I had driven about 2000km on it, which is around 1,200 miles of engine time. I got the oil changed, then i got it changed at the 1 year ownership mark (6 months later, and maybe another 1.500 miles of engine time?). Now I'm just gonna change the oil once a year. I figured two lower engine on time oil changes at the outset is a good start for the engine. It turns on so little, that as long as the additives are good til the 12 month mark, and its not super contaminated, it will be fine. I check oil level once a month and I look to see if it is visually getting water contaminated from the cold weather and not hitting temp often enough. But as long as that's not an issue, I'll just do once a year oil changes from here on out. It will probably be something 2,000-2500 miles a year at most on the engine if I do family road trips. The rest on EV mode based on our current usage. Warranty clauses don't want you to forget. My dealer offers extended engine and transmission warranties if you get it serviced there for oil changes, and within a month or 1500 km of the oil change interval (or transmission fluid changes). And the Toyota warranty has a similar clause for the 5 year powertrain period. Go too long with a gap and you can have troubles.
No. It could be argued it's hair splitting, though. Keep in mind there are other factors besides miles, accumulated moisture in the oil over winter. A story: I worked for a while in a small, steel-detailing office. We detailed everything from miscellaneous steel to whole buildings, hospitals, schools, ferry terminals, anything and everything. There was one job, purely ornamental, architectural steel, a cinder block fire station, and the architect had spec'd some "structural looking" curved wide-flange beams wrapping around, near the eaves. There were various lengths of this stuff, including one that was a mere foot long. On that one I think the deflection due to the curve was about 1/8". I drew it all up, and handed it to the checker, an elderly guy, someone I gradually came to realize as being in MENSA territory, very bright guy. When he gave it back to me he pointed out that foot long piece, commenting: "I signed off on that as-is, but a short piece like that, you could just leave it straight; up there in the air, nobody will be able to see the difference". (I'm paraphrasing, but words to that effect) That stuck with me. Addendum: the flip-side to that: the fabricator shop will likely roll one or two long beams for this, then cut them up for the various required lengths, so no skin off their noses to have a (curved) foot long piece. What we could have done: left the foot-long piece drawing as-is, but add a note, something like "THIS PIECE CAN BE LEFT STRAIGHT, AT SHOP'S DISCRETION". That way, if that foot-long piece necessitated them rolling yet another beam, this would allow them to avoid that.
GM has said going 2 years is okay with the Volt. Even then the oil may still be good. The concern with a PHEV not using the engine often becomes water build up in the oil, thus why GM doesn't go longer. That said, once a year will generally be easier for most to keep track of if the car isn't doing it for them.
Right. But seeing as the factory suggested oil change interval on the prius hybrid is 10,000 miles, and I am changing my oil (on exactly the same engine) on my prius phev every 5,000 (ice) miles, it sure seems that I am playing it extremely safe. And I understand the warranty considerations; during the warranty period, I will comply with those.
Yes, good point, I am watching for water build up. But, since we use our ICE for long stretches on the freeway somewhat regularly, we typically get the oil hot enough to boil off any accumulated water. Or so one would think.
Yeah but the service manual says "1 year or 10,000 miles whichever is first". The additives do break down over time, so that's probably why they kept the 1 year marker to be safe. Realistically, if you do 1 time a year instead of 1 time every 2 years, over 10-15 years thats what, 7 oil changes? That's nothing in the total ownership cost of a vehicle.
Yeah, I am not doing this to save money (well, maybe to save some time). I just feel bad about dumping perfectly good synthetic oil. Yes, agreed, the oil additives don't last forever, but I wonder how long do they last on an engine that gets very few miles? Surely not 10 years. But it would seem that they would be perfectly good for 2-3 years? What do you think?
The additives don't break down*, they get consumed. Anit-wear compounds(what the GM oil monitors calcs are based on) are only used while the engine is running. Detergents/acid neutralizers keep potential sludge particles suspended in the oil, and counter the acids that form when water mixes with those particles to form acids. While water can get into the oil without the engine running, but those particles are formed during the engine operation. *Well, they'll break down with the rest of the oil through oxidation. Which isn't fast process without the high heat from the engine.
You cold send the oil in for testing. I'm just gonna do it every 12 months because the time isn't SO huge that once a year will matter to me. Better than when we needed to do 3 month oil change intervals for people with 2 cars in the driveway That was expensive and time consuming. Even on my old 2003 matrix, it drives so few kms I do full synthetic and once a year changes and the oil looks good and its been driving fine for the 5 years I've done that. But the one time I left it to closer to 18 months (because of covid and putting maybe 3,000 KM - not even miles on it) the oil was dark and gross looking. Yes, its an older, less clean and efficient running engine. But still, it was a bit surprising.
No one wants to be liable for straying beyond the lowest common denominator. That's why everyone uses the most conservative recommendations possible. It could be the basis of a lawsuit if someone blows an engine and blamed it on someone's less-conservative advice. When I'm doing oil changes, I have stretched the interval by 2 or 3 times; never had an engine wear out either.
It's all the perspectives and observations that make the forum valuable. I hadn't even been thinking about running the ICE a bit more often initially to bring to the front any infant mortality or other issues. Interesting conversation about additives, water, and time. I'm having a interesting enough time just getting used to all the different aspects (different menus, settings) of the car, so for now I'll take the easy route and say yearly changes. I'll have to rotate the tires at 5,000 miles, I could change it then, we'll see what happens first!
I went with a non-synthetic for our Sable; it was doing around 3000 miles a year. It got cold and windy after I changed the top mount filter on the HHR, so decided to put off draining the oil until next weekend. After 300 miles of driving the old oil through the new filter, the black oil went back to brown. An option for PHEV oil that hasn't seen much use is to find another use before disposing. Like in the lawnmower, or as bar oil, or even the extra car that gets low use.
I had a patent counsel for BF Goodrich lose his mind when I suggested leaving full synthetic in a car for more than a year. He had just explained to me the miracle of a synthetic they can put into a race car that will last an entire race under lots of heat and pressure. He explained that part of the reason to change out the oil, even oil that had all its lubricating properties intact, was to remove the acids in the old oil that he maintained would etch the metal in the engine.
The first oil change matters more than the subsequent oil changes. If I had a brand new car, I'd change the oil at 5K miles, or perhaps even sooner to get rid of the extra metal that's going to be wearing off of the rings, cylinder walls, and anything else left over from the manufacturing process. I know Toyota says it can go 10K miles between oil changes, but none of the mechanics do. Toyota wants me to buy a new car more often, because that's good for Toyota, not me.
Toyota also says that because, since the inception of ToyotaCare around 2011, they're now paying for those early oil changes. Switching from 6m/5k changes pre-2010 to 1y/10k post-2011 cuts the number of oil changes Toyota pays for in half. That's also good for Toyota and not for us.
i figured i would go by what the owner's manual states and let toyota service it as recommended. I am hitting the easy button on this one
I'm probably over thinking this but I am a little curious if buying a new car out of state (say to get the spec and color you want) and driving it more than 3-4+ hours home hurts the engine at all since the break-in says the rpms should vary for a while when new. :: shrug ::
