Best of Deals Car Reviews Repair Shops Cars A-Z Radio Show

Increased oil change intervals

So, many Toyota/Lexus cars from the 90’s have 5000 mile oil change intervals.
My fairly new Toyota says 10000.
Is this due to better oil, or cleaner running engines,
or just hype to sell cars?
I am using Mobil 1 in all of them.

The cars can handle it. I can’t believe that Toyota would increase the oil change interval just to increase car sales. IMO, the number or Toyota buyers that would look at an arcane number like that is small. Toyota engineers tested their engines and determined that they can go that long and provide satisfactory service for the lifetime of the car. They would not trade a small increase in current sales for an eventual loss in sales when the engines wore out prematurely. Toyota is a lot smarter than that.

1 Like

Oh boy. Oil thread. Does your car spec syn oil? Such as 0-20? Maybe it uses 5-20 which typically may not be syn. Though quite a few new cars use 5-20, 5-30 or 10-30 AND do use syn. I think if car is spec’d for syn, than computer knows this and may recommend longer oil change intervals. I don’t think going 10k miles on Dino oil is a good idea

You can guess if you want. If the Toyota engines spec mineral oil and give you an oil change interval, it means to me that they are willing to risk losing their customer base if it doesn’t work out right. It also means that they lowered the risk dramatically by thoroughly testing the system to make sure it works in a wide variety of conditions. Since many engines require 0W20 or so oil, synthetic or semisynthetic is the only way to get there.

1 Like

So I am guessing Toyota does not have an oil life monitor (OLM)?? Does the interval also say “or one year” in the manual? Hard to argue against Toyota knowing its business.

Yes, oils have gotten that much better. Engines also don’t pollute themselves as badly as they once did. I’d feel quite comfortable at 7500 miles and one year with synthetics. I’d feel more comfortable if the car had an OLM telling me to change and use synthetic to boot.

Our old 2010 4 cyl Camry had a 5k interval? We got letter from Toyo saying it was ok to go 10k. I am pretty sure it was a letter and not an email. We did use syn in the Camry. Don’t recall weight.

Im hoping that, in addition to recommending longer intervals, manufacturers are also requiring synthetic oil, which should stand up to heat stress better and last longer.

OK, I should be more specific. My son has a 99 Lexus LS in which we put Mobil 1. Should we go for a longer oil change interval than initially specified for that car?

Forty years ago I serviced Ford and Chevrolet vans operated on parcel delivery routes of 300+ miles per day. Monthly service meant that the trucks accumulated 6-8k miles and at that time synthetic oils weren’t in common use but the engines ran well for hundreds of thousands of miles… FWIW.

Not an expert, but the engineers who designed the car are. I’d never go beyond the spec, even when switching to synthetic.

Oil is cheap, engine rebuild is not.


I’d do whatever Toyota recommends in the owner’s manual, regardless of the cost of oil and filters. The engine may, or may not, be identical to the ones used today, except for displacement. If your son wants to extend the oil change interval, he can have the oil tested at the end of the 5000 mile interval. That will show the remaining oil life.

sounds more expensive than changing the oil.


You’re probably right, @BillRussell. After a few changes at an upward-revised interval, the cost may equalize. I don’t get oil tests and use the OLM. I get the oil change between 20% and 15% remaining life. I tell my children to do the same.

I owned a 2011 Toyota Sienna which I bought new in the Spring of 2010 when the 2011 Siennas hit the show room. Toyota specified 0W-20 full synthetic. The manual said to change oil every 5000 miles, but I received a letter from Toyota stating that the oil change interval had been extended to 10,000 miles. I changed oil every 10,000 miles. I sold the 2011 Sienna to my son last month. In the 92,000 miles I drove the Sienna, I never had to add oil between changes. I replaced the 2011 with a new 2017 Sienna and I’ll follow the 10,000 mile oil change interval.
I do think synthetic oil is worth the price in extending engine life. I have an old push mower that I purchased new in 1992. The engine started using considerable oil and I was fogging for mosquitoes when I mowed. Two years ago I switched from straight 30 weight heavy detergent to 10W - 30 full synthetic. The oil consumption dropped by 75%. I got about 2 seasons more out of the mower. Unfortunately, the last time I mowed a week ago, the mower started smoking again and the oil consumption went up. The mowing season here is about over, so I won’t have to go mower shopping until next spring. The 10W - 30 full synthetic was $2.79 a quart which was $1 more than the 30 weight Dino oIl for $1.79 a quart in the house brand at my local Rural King store. I think the $ 2 extra for 2 seasons of mowing was money well spent.

1 Like

For my mom’s 2010 Prius the long time mechanic’s are using a 7,500 mile interval or thereabouts but the usage of the vehicle should factor in how often you go between oil changes. 5,000 miles was the interval when she took delivery but Toyota later changed it to 10,000 miles. Her previous '90 Mazda would get an oil change at around 6,000 miles…

Both engines and oils have improved dramatically in the last 20 years. Having said that, Toyota has always been rather conservative in these things.

My 2007 Toyota called for 5W30 regular mineral oil sold at that time. Since then I have received bulletins that 5W20 and 0W20 (a full synthetic) are OK. A synthetic 5W20 is a much better oil than a 5W30 mineral oil.

So the increased drain interval makes sense.

However don’t use a cheap mineral oil from a discount store; it will not fully protect your engine. Use only oils recommended in the owner’s manual.

From what I’ve read here on the forum over many years, an important factor in oil change mileage and time intervals is typical use of the car.

Prime example, most of my driving is considered severe use on the engine because I’m a low annual mileage driver with the majority of my driving being short distance with multiple stop and restart cycles. I may drive only 7 to 15 miles total but make stops at three to five lications such as grocery store, library, veterinarian.

So I maintain all service on my car at the extreme use recommendations; oil changes, transmission service, etc.

I also make a point of taking the buggy for an extended spin, including at highway speeds, once a week and checking the oil dipstick every week or two weeks at the longest.

And since my urban driving from stoplight to stoplight has the transmission shifting up and down through gears far more than would mostly highway driving, again I make sure to adhere to tranny service intervals the owner’s manual stipulates for extreme use.

Further, I expect to get moderately shorter battery life and possibly shorter life of the starter than normal.

It all gets back to reading the owner’s manual for your particular vehicle and noting what is or isn’t considered average versus extreme use and adhering to the applicable service recommendations therein.

1 Like

As long as the oil container has this symbol on it,

you can buy the oil from Bobs’ Bait and Burgers, and it will fully protect the engine.


1 Like

I refuse to argue about this anymore. I use Mobil 1 and change at 5000, regardless. I change my mower with synthetic at about 25 because it is dirty even though the book says 50. My mechanical genius BIL says once a year. So rather than argue or try to convince someone else, I just do what I want. Maybe a waste of money but it helps the economy if nothing else.

1 Like

There is more to oil than Service SN; It mostly refers to the additives. If the base stock is not up to scratch the oil will fail in extreme service such as heat, trailer towing and extreme cold.

An SN oil will not suffice for a European car which has the much tougher specs, and costs more. Even Mobil1 has an American and a European version.

I agree that for easy and no stress driving, the SN spec is OK for American and most Japanese cars.