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Synthetic Motor Oil

I recently moved and have a reasonably long commute - 60 miles round trip. There are about 70,000 miles on the odometer. The change oil light just came on and I am thinking about using synthetic oil for the first time. One brand, I don’t remember which, bragged about a 300,000 mile guaranty. Is it worth the cost?

Nope, not in my opinion.

In over 40 years of car ownership, some for hundreds of thousands of miles, I’ve never worn and engine out…and I’ve never used synthetic. As long as your Owners’ Manual doesn’t require synthetic, then I don’t believe the expense is justified.

Unless, of course, you sleep better with synthetic oil.

Your commuting distance means the engine will likely never sludge up if you change oil and filter regularly. Since oil change intervals can’t be stretched very much without voiding the manufacturer’s engine warranty, I would stick to a good quality mineral oil, change oil every 5000 miles, and save a lot of money in the process.

Synthetic oils really shine in very dificult environments, such as extreme cold, extreme heat and heavy engine loading such as trailer towing.

Your type of driving with good maintenance will allow your Toyota to reach well over 300,000 miles without an overhaul IF you maintain it by the book and regularly check your oil.

If I was in your shoes, and lived in one of the Northern states, I would have a block heater installed and still use regular oil with a 5W30 viscosity. That will result in less engine wear than using 5W20, which Toyota is now pushing to increase the CAFE milege ratings. I categorically would not use this 5W20 in the Southern states.

Happy motoring till your reach 300,000 miles.

What is the model year of your Sienna? Some models were known for having sludge problems. If yours is one of those, I would make the switch, but if not, I would stick with what you have been using.

It’s a 2006. According to Consumer Reports, 2002 - 2005 were the problem models.

The motors that last 300,000 miles without serious issue have a reasonable design, a bit of luck, and owners who actually change the oil in a timely basis.

The major hurdle to engine life is changing the oil in a timely manner and not being lax. The type of oil and brand means little.

Properly using a decent-quality 100% synthetic (filter changes & sump top-off every 5k miles and oil & filter change every 15k) will cost you about half as much as running high-quality petroleum oil and a quality filter with 5k changes.

Forget that flippin’ light, pay attention to miles/hours, why trust your engine to $1.50 sensor that’s questionable to begin with? That’s the problem, automotive engineers will put a worthless sensor and lamp in the car but absolutely refuse to upgrade the filtering system - been using the same system since about 1903!

First, trust the light, they work. If you are going to change the oil within a week of the light illuminating, then just use conventional oil. The economic advantage to synthetic is extended oil change intervals.

The oil change indicator does not use a sensor, it uses a program that counts the number of revolutions of the engine, time the engine is running, and most important, the number of hot shutdowns. For this reason, the program is for the recommended oil. If the recommended oil is conventional oil, then you will be on your own if you decide to go beyond the interval indicated by the light and that could be not so good.

Now if the oil specified is a synthetic oil, then the light is programmed for that oil and using conventional oil would be a problem.

As fro the 300,000 mile guarantee, better read the fine print. I think you will find that you have to use this oil from the very first oil change and keep extensive documentation to prove your claim. In addition, the compensation is probably prorated so you would likely not get much back unless the engine suffered an oil related failure early in its life, very unlikely.

We’ve had numerous threads on the subject of extending oil change schedules with the use of synthetic rather than dino. Most of us believe we change oil to extend the life of the engine, not the oil. Extending the oil changes because one ios using synthetic does not extend the life of the engine. Synthetics are just as subject to particulates, dilution from blowby, and most all the other things that dino is. Most of us recommend against extending oil changes by using synthetics.

I have yet to see a single study that ties a difference in engine longevity or wear due to the use of synthetic. Until I do, I do not recommend extending oil changes. There is convincing evidence out there that failure to change oil affects engine longevity. Nor have I ever seen a single credible study that proves that synthetic improves gas mileage. In the lab synthetic’s more consistant molecule size may be shown to have better lubrication properties, but it’s never been shown to affect gas mileage. If one changes oil per the maintenance schedule, synthetic does not save money, one spends more.

I would expect someone selling Fram products to make the recommendations you’ve made. And I’ve always been satisfied with and continue to use Fram products. And I respect that these are the contentions of the perveyors of synthetics. But until I see evidence that these contentions are true, I’ll continue to recommend that oil be changed per the manufacturer’s recommended schedule and that dino be used unless the manufacturer recommends synthetic. Oil is cheap; engines are expensive.

In that case, I would stick with normal conventional oil.

Can the spam, Fram man.

If you extend the interval beyond what is recommended in the owners manual then you run the risk of voiding your warranty.

What’s your resume? Mine is 15+ years fleet PM and 25 years heavy industry PM. No “opinion”, just the facts - can’t handle fact, don’t blame me.

Have an independent third-party pull an oil sample, end of discussion on warranty issues - BTDT.

Actually, the post I was responding to was from the Fram guy and seems to have gotten deleted.

However, Mark, I love facts. But an opinion or a perception is not a fact, even if it’s long-held. Facts are proven only through the hard work of analysis and testing. When long-held beliefs or opinions get subjacted to actual controlled analysis, they often fall short. That’s the way science works.

Post some facts and I’ll be happy to read them. Until I see some my opinion will remain as it is and based on my own experiences. I respect that yours is different.

Or you could simply follow the manufacturers’ required oil change schedule.

Warranty criterion cannot be voided in this manner. The warranty says you must follow the manufacturer’s recommended oil change schedule or you risk voiding the warranty. Period. Warrantys are unilaterally written documents. They’re not subject to negotiation.

Some people will go through enormous aggrevation, cost, and effort to avoid doing somethng as simple as following the required maintenance schedule. And then they convince themselves that they’re saving money. They try to convince others too, but they really don’t.

Sorry, Mark. The poster I was responding to had his post removed. I wasn’t responding to you.

By the way, Whitey, I loved “Hook”.

Have an independent third-party pull an oil sample, end of discussion on warranty issues - BTDT.

That isn’t necessarily true. If you are filing a warranty claim, and you extended the oil change frequency beyond what the manufacturer recommends, a used oil analysis could hurt your case more than it helps. They could use it to prove you didn’t follow their recommended service interval, which is all they really need to do. Whether the old oil was the cause of the malfunction is irrelevant when it comes to voiding a warranty. This is a legal issue, not a mechanical issue.

been using the same system since about 1903!

Lets see, that puts you at about 108 years old.  How long did the candles in the head lamps last back then?  How did the brights work?  ?