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Oil Change Timing

I have cut down on the mileage I drive my 2008 Toyota. I only need to drive it about 7500 miles a year. Is the time to change the oil determined pretty much by mileage or does age of the oil a determinant on when the oil needs to be changed?

Please tell us why you don’t want to follow the instructions provided by Toyota in your owner’s manual and we’ll go from there.

As lion9car implies, just follow what your owner’s manual says & take time to mean as much as mileage if it so specifies.

And keep in mind that things like oil changes are cheap. Engines are expensive.

I drive my 2006 Toyota ~4000 miles a year.
So I change the oil every 6 months.
Simple as that (6 months or 5000 miles).

If you use full synthetic oil, live in a fairly warm climate, and do mostly highway driving, you can probably get away with changing it once a year. But oil changes are pretty cheap. Even at $50 for an oil change, doing 2 a year shouldn’t kill you. If you have any warranty left on the vehicle, I would strictly follow the owner’s manual recommendations though. Also, some Toyota engines are prone to sludging up if the oil isn’t changed on time. Doing that extra oil change per year is cheap insurance that this won’t happen to you.

I’m in the process of changing the oil & filter in my 2007 Yaris right now. It’s draining at the moment. The last time I changed the oil was in January of this year. I’ve only driven 992 miles since then.

(slightly off-topic) I wish time was a problem for me. I did my 130K change on 18 Jun…did my 135K change today (23 Jul).

6 months or 5000 miles, whichever comes first. Clearly, in your case, 6 months comes first. As so many have said (in many, many threads here), oil changes are cheap, when compared to a replacement engine. Warranty or not, you should stick with the schedule. It just makes life SO much easier. Pay attention to the other things there, too. Almost all of them have a time limit to them…and it’s there for a reason.


If the car is driven on short trips where the engine never gets up to full temperature where it can burn off condensation you should probably change it by the time/months even if it hasn’t been many miles, but if the car sits without being driven the oil is doing nothing but sitting in the oil pan and shouldn’t need to be changed. I’ve got one car that is basically driven on long trips, it’s a '97 model with 32K miles on it and I change the oil every 3000 miles and don’t worry if the oil has been sitting in it for 1-2 years. My car is 14 years old and has had 10 oil changes since new.

I would use 6 months unless the severe interval suggested more often.

My current 2004 WRX I only do 6k per year and unfortunately end up with 3 oil changes per year due 3.75 month/3750 miles interval. Fortunately it only needs conventional oil so the $30/pop is tolerable

The problem is condensation destroys your oil. The only real way to tell change interval is sending a sample to a lab which I think is a bit much. Otherwise its pure guess and conjecture as its a combination of many factors. The severe interval takes this into account.

Like circuitsmith, I drive very low miles per year. though I change my oil every 4 months, because that’s what my owner’s manual says to do; 4 months/5k miles. If I waited for miles, I’d most likely coke my turbo in no time. I pay $60~70 a pop for full synthetic, even though my owner’s manual doesn’t specify; I figure the extra protection is worth it, considering the nature of turbo engines.

There are two situations. First, while the warranty is still valid. In that case, don’t think, heh, heh, follow the owner’s manual as to time or distance, whichever comes first.

After it is all yours, there are other options. My car is mostly driven on the highway, and I am in the heart of Mexico, outside the snow zone. A year and a half ago I let my 2002 Sienna with (I forget the mileage, probably over 150,000 miles) go to 8800 miles,without changing the filter, on Mobil-1 Extended Performance, because I wanted to know the truth, with all the various guesses and opinions on this board. When I drained it, I sent a sample to Blackstone.

All parameters were good for maybe 10,000 miles. Contamination; additives; everything still good. Now, I aim at a change around 8,000 miles. It has been a while since I checked the manual, but it seems like my car recommended the change every 7,500 miles, so this is actually pretty close to recommended, as well as what the oil test would recommend.

However, that is only true for my car in its condition, no blow-by, no coolant leakage, rings solid. And for my driving pattern, mostly highway, outside the snow zone. Another car may have totally different results.

But, I do agree if you don’t have your oil tested, you are guessing. If you are guessing, it is better to change too often, rather than not often enough. Oil costs little in comparison to the motor itself.

There are more reasons to have the oil tested than oil life. That oil test tells you so much about the condition of the motor, bearing and piston and valve train wear, integrity of cooling system, and more. It’s like having a microscopic mechanic walking around inside your motor. I will have it done from time to time as a motor check, more than an oil test.

I would never recommend testing oil to see if it needs to be changed as a few do. It is cheaper to change it. Have it tested both cold and hot seasons, and then remember what you found. Check it to see the condition of the motor from time to time.