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Royal Purple High Performance/Extended Life - How Many Miles can I go before next oil change?

I have a 2005 Toyota Camry and I just put in the following into it.
Oil - Royal Purple 51530 API-Licensed SAE 5W-30 High Performance Synthetic Motor Oil - 5 qt.

Filter - Royal Purple 10-2840 Extended Life Premium Oil Filter

On the Royal Purple website ( it states “Nowadays, many carmakers commonly recommend an oil change interval of 5,000 to 7,500 miles, or sometimes even 10,000 miles or more, under ideal operating conditions. Certain premium products like Royal Purple API-licensed synthetic engine oils allow motorists to travel as many as 12,000 miles as the recommended oil change interval. Even more amazing, Royal Purple HPS™ synthetic performance upgrade street oils allow up to 15,000 miles in between motor oil changes.”

So I can go 12,000 miles or 15,000 miles within a year before I need to change it? Also on the amazon product page for the oil I put in it states the following:

“Can Royal Purple Motor Oil Be Used In Older Engines?
Yes. Mileage and/or age is not a factor when used in a mechanically sound engine. In high-mileage applications, it’s recommended running a minimum of two short (3,000 mile/5,000Km) intervals before extending the oil drain intervals. This will enable Royal Purple’s high solvency to remove existing deposits gradually; such deposits can restrict oil flow, if excessive, as well as reduce the oil service life significantly.”

Is it really necessary to do two 3,000 mile oil changes when switching over to Royal Purple? I have had used synthetic oils in the past, just never royal purple. I have just over 155k miles on my car.

At no time should you ever extend an oil change interval beyond the mileage recommendation in the owner’s manual or maintenance schedule. Or beyond a period of 12 months, whichever comes first.

Who do you trust more when it comes to the longevity and operation of your engine? The team of technical engineers and legal consultants who designed and built your engine, or an oil company?

What exactly are you trying to gain?


Do NOT exceed the oil change intervals stated in the owner manual

That means oil and filter change every 5K or 6 months, whichever comes first

No ifs ands or buts

Who cares what Royal Purple says . . . ?!

They didn’t design your car

By the way . . . are you seeking guidance?

Or do you only want somebody to agree with what you’ve already decided to do . . . ?!

If it’s the latter, just say it

Of course, you’re the one that decides how to maintain your own vehicle, but not everybody will be in agreement with that all the time


Do the 3000 mile quick change if the oil gets very dirty very quickly and/or you find the car uses a quart in 1000 miles or so.

I would not go beyond a year, and not more than 7500 miles between changes.

Full disclosure, I use Royal Purple in my Mustang. It is expensive but it runs cooler than other synthetic brands when doing track days.

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I understand your point about following what the manufacture of the car says for the oil change and not the manufacture of the oil or filter.

What is the point of the extended life oil and filters if your supposed to change your oil per the car manufacture’s recommendation regardless of the oil and filter you use?

And yes I’m seeking guidance. Not just to hear somebody agree with me.

Advertising to sell a product , period . Ignore that and go by the time and miles in the manual .


So I should just use the cheapest oil (with he correct viscosity) and filter I can find for my car?

There isn’t any added benefit in “high mileage oil and filters” if I just change it every 5,000 miles, it’ll just suck money out of my pocket? Not all oils and filters are built the same, but it doesn’t matter?

Maybe the high mileage oil and filters will better lubricate the crank case, but is it worth paying all the extra money if I just change it every 5,000 miles or 6 months regardless of the oil or filter I use?

Bingo , we have a winner . Besides did you not recently acquire this as a used vehicle ? If so you don’t know the actual history of service so don’t make it complicated.

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Yea I got it as a used vehicle about 5 years back. I under that you should just just listen to the manufacture says.

I’m an engineer myself. Let me ask this question. What is the requirement for when oil should be changed?

I filled up sample cups of multiple different oils from different mileage. I don’t provide the oil manufacture, the car, or the mileage. I just label the cups A, B, and C etc…

How do I scientifically test the various oil samples to determine if the oil needs to be changed or not?

Mileage seems arbitrary. Based on driving conditions, maybe you should change your oil sooner than 5,000 miles. What is the technical requirement for the properties that the oil must exhibit to still be considered “good”?

Example break fluid, you can scientifically test the percent of water in it via a tool. If it reaches a certain percent it needs to be changed. Plain and simple test.

Why do you even care ? That is why the people who made the vehicle list service and severe service in the manual . And you are an engineer and you misspell brake ?

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Well that’s the point. There is no point. Use a good quality oil and change per recommendation. The rest may be marketing but if it helps with racing like Mustangman, fine. Still gotta change it though.

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I have found that if you can go 5000 miles on conventional oil, you can safely go 7500 miles on a synthetic. Past that, things get risky. The reason for the extra miles is that synthetic oil tolerates heat better. Heat is the main factor in the deterioration of oil and the most damage is done in the ten minutes or so after you shut down the engine. A thin film of oil is trapped in the engine and it must absorb all the heat from the engine as it cools down. It does not have oil constantly flowing to draw the heat away like it does when the engine is running.

That only affects a tiny amount of oil and on the next start, it gets flushed away with fresh oil, but it mixes with all the oil in the pan. After a period of time, more and more of this trapped oil is getting mixed in with the oil in the engine. This trapped oil does weaken the remaining oil a little, but it is cumulative. Eventually the oil in the engine can’t tolerate the heat as well as it could when new because of the slightly broken down oil mixed in. Now it begins to suffer more on each cycle and break down even more. If allowed to go too long, it begins to thicken into a substance called sludge.

If the sludge is allowed to build up, it restricts oil flow even further causing more damage to the remaining oil to the point that it can crystallize forming coke. Coke is a gritty hard form of carbon and it will really damage your engine.

But you just need to change the oil before it breaks down tot he point of doing any damage and for most synthetics in most engines, that is around 7500 miles.

In many “independent tests” that you can see on YouTube where people film their own tests, they will rank oils based on their criteria. Royal Purple usually does pretty good on these test, especially in the wear tests. If it really is as good as these tests indicate and it does have less wear, then theoretically your engine would last longer and that is where the value would come from, But that value is lessened if you start using it in an older vehicle which may already be near the end of its life.

It would also be of less value to a new car buyer who does not plan on keeping the vehicle for as long as possible. If you aren’t going for the million mile club or something like that, then any oil that will get you as far as you need it to is all you need. For most of us, all the major brand oils that are API certified will do.

You can send oil samples to places like Blackstone labs… I think that is the right name…and have them analyzed after 5k, 7.5k, 10k for additive breakdown and wear particles.

You ask about cost… Royal Purple is expensive stuff, Mobil 1 less so, conventional oil even less. RP is trying to justify its greater expense with longer change intervals. I am not comfortable with that on a older engine.

I buy it because my oil temps reach 245 F at trackdays and new engines are expensive.

So basically the point of this article is that regardless of what oil you use, given the same engine, the wear is the basically the same, regardless of the type of oil that you use. Any difference is negligible. Very interesting. That is what the data seems to suggest.

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I’d use synthetic if recommend by the carmaker or if I lived in a very cold climate (or for extreme use, like @Mustangman describes). Any of that apply?

Not really. But it can get in the single digits (positive) degree F where I live during the winter. I’m not sure if that would be considered extreme cold.

If your car is kept outside then it is to me. Synthetic has better cold temp flow. But I’d use ‘regular ‘ synthetic from a big box, like Mobil1.

Because there are some cars that have 10K or longer oil change intervals

Yours isn’t one of them

I wouldn’t go that far . . .

I would suggest at least a name brand oil filter . . . wix or fram, for example

As for oil . . . if you’re a Costco member, conventional oil and synthetic oil are on sale several times throughout the year, but never both at the same time

Not worth it

Is your engine consuming a lot of oil . . . ?!