Castrol synthetic oil 5w30 on 2007 4Runner

Not if you want to keep the vehicle long, unless it is all light duty highway driving (like 90kph (50mph) with no load at 70 degrees F and

100 miles or more at a time.

Call me old fashioned but I'm a firm believer in using the best oil and frequent oil changes. There is no cheaper insurance for a modern engine than high quality fresh oil. I use full synthetic in my Sentra and change it every 3000-3500 miles. Is that ultra conservative? You bet. My last Sentra went 333000 miles on 2000 mile oil changes with conventional oil and the engine was still running fine. Ditto for my previous Datsun whose engine was running fine at 230000 miles when I junked it because everything else was failing. Skimping on oil changes is penny wise and pound foolish. Good luck. Al

No, in 2004 Toyota specified 5000 mile oil changes for all its vehicles, including those in the Lexus division because of sludge concerns. If 10K miles were the case, then Toyota would have said use Castrol and go 10K miles.

agreed. my 86 1/2 supra has 190,000 on it and runs like the sporty beast it was made. motor growls and runs like new. just passed another ca smog.

Not if it's still under warranty.

Your best bet is 5K dino oil changes during the warranty period. Synthetic has absolutely no advantage in 5K oil changes (unless you live where it's extremely cold).

Once the warranty expires, you might try synthetic, and do some oil analysis at 5K, 7.5K, and 10K to see if there is any difference. You can get your oil analyzed for about $28. If this saves you from needless oil changes it might be worth it, though in reality you're best option is just to follow the factory recommendation of 5K dino oil changes, which is already very conservative.

I would not put Purolator in the good class. Unless the only other choice is Fram; then a roll of toilet paper would be better.

No, it's insanity.

Puro makes good filters and crap filters. The Pure1 is in the good class

You can leave oil in YOUR car as long as you want. I'll change mine every 5000 miles. I generally drive my cars 'till they are 18 years old and I've only had ONE in 40 years go to scrap with a dead engine.I don't rebuild them either.

Buying insurance is insanity too - you have to loose to win - and life insurance in particular - you have to DIE to win.

I'll be insane. If you want to call it that.

(by the way - I'm a mechanic and I've seen firsthand the results of "extended drain".

That's great. Just don't change it every 3000 miles, with synthetic base stock or petroleum base stock, and think that it's providing an iota of benefit versus 5000 mile changes. It may make someone feel good to change their oil more often than necessary (recreational oil changing) but it doesn't do anything for the engine. Period.

I've measured the compression on vehicles I've had for 10 years and 13 years with 5K oil changes on dino oil and they've been close to the top end of the range of compression.

You make it sound like an 18 year old engine that still runs is some sort of anomaly, but it's not. Engines that fail usually do so because they are run without oil or without coolant, or because of a design flaw (i.e. the Saturn engines that were prone to head cracking). Not because the oil was changed at 5000 miles versus 3000 miles, and unrelated to the base stock of the oil.

One possibility is repeated short-term use of vehicle without engine reaching full operating temperature. Acids that form from cool down condensation never have a chance to heat up and fully evaporate and they can prematurely corrode precision bearing surfaces.

nb

No, I don't use a Frantz Toilet Paper Filter. From what I heard from old-timers these filters actually do a pretty good job.

Frantz toilet paper filter:

I was talking about the excellent PureOne filter. The top-ranked filter on the shelf is 99.9% efficient based on ISO 4548-12. Even the Pureolator Classic has 97.5% efficiency. If you know a more efficient filter let me know.

Purolator PureOne 99.9% efficiency, ISO 4548-12:

Purolator Classic 97.5% efficiency:

That's a good point. Most people don't keep their cars for more than

3-4 years. At least that's when Toyota starts to send you letters trying to get you into a new car/truck. So I'm sure some people don't have to change oil. ;) ;) ;)

When do they send those letters?

We've had a Camry for 13 years with no letter. A 4Runner for 8 years with no letter. I had a Land Cruiser for 16 years with no letter.

It's difficult to understand why some people are unable to look at all the scientific and empirical evidence, and how they let emotion lead them to waste both money and resources.

I don't know where you live, but in California, people tend to keep their Toyota's and Honda's far longer than 3-4 years.

except for pennzoil. it makes sludge and kills engines. even with 3k changes. it's the draino of oil.

what are the lame ones Auto Zone & Checker peddle (wedged in among all the vomit orange frams)?

Frantz toilet paper filter:

I would not put Purolator in the good class. Unless the only other choice > is

The compression may be perfect (or even higher than normal) and the engine may still be severely damaged. Carbon buildup due to oil consumption can increase compression significantly - enough to hide the effect of both bad rings and bad valves in extreme cases.

Add to that the fact that bearing wear does not affect compression - and even camshaft wear will often not give any indication of trouble on a cranking speed compression test. The current "coking" issues will not necessarily affect compression before the engine fails.

What percentage of vehicles sold 18 years ago are still on the road? What percentage of those sold TODAY will still be on the road in 18 years? Want to bet it will be those that were maintained? The failure of Chrysler, Honda, and Toyota engines due to "sludge" or "coking" can be 100% prevented by changing the oil often enough and running premium quality (usually this means synthetic - but some dyno or synth blends also qualify) engine oil. And depending on the driving conditions, 3000 miles MIGHT be the required interval (low mileage, short trips, temperature extremes, etc) with a standard oil.. The additive package used by the refiner is at least as important as the base stock - but that is not to say a synthetic base may not be advantageous.

I think it is safe to say that GENERALLY an engine that fails fails for one of 2 reasons. Neglect or design. The odd one dies of "old age" at extremely high mileage due to wear and fatigue, in spite of exemplary maintenance and superior design.

ANd now Quaker State and Penzoil are the same company. I stopped using Quaker years ago after opening up my engine and finding a heavy WAX coating over everything. I never had a problem, or failure using their remium oil, but I could envision that coating restricting oil galleries etc. I stopped using Penzoil after the first time - when the oil light on the Dodge van came on at highway speeds less than 200 miles after the oil change. A quick change back to Castrol GTX (my preferred oil at the time) and the light never came back on. That oil was as thin as kerosene when it was drained.

Currently running 10W40 Castrol in the 96 Mystique (135000km) and synthetic in the 2002 PT Cruiser.

4 changes a year on the mystique, 4 on the Cruiser. The cruiser gets almost double the miles on it. (33000km last year)