Which would you choose? 12k mile OCI with a 100% synthetic or 5k mile OCI with conventional

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I'd like to know what members of the BITOG forum would choose for their vehicles. (Let's assume that cost is equal.)

A. 12,000 mile OCI with high-quality 100% synthetic oil (such as Amsoil signature series, which is rated at 25k miles) + very high quality filter.
B. 5,000 mile OCI with generic conventional oil + average quality (low cost) filter.
 
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A

I would prefer to use high-quality 100% synthetic oil which is Royal Purple + very high quality filter which also happens to be Royal Purple 💜
 

Samuraidog

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How often do you want to crawl under your car? Or what is your time worth?
Let's assume that number of times crawling under the car, worth of time, environmental impact, etc. is a non-factor. I'd just like to know which you'd choose if only given one option for the rest of the life of your car/engine.
 
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If the Amsoil is rated for 25K and your paying a premium for it then why would you change it out at 12K ? At least run it 20K and change the filter every 10K and add a quart.
 
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I go with A.

But I'd change at 10k intervals. It's easier to remember cardinal numbers like 10k, 20k, 30k, etc. Who wants to remember 12k, 24k, 36k, blah blah.

Bottom line, I'd check owner's manual to see if going that long is allowed.
 

Samuraidog

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Insufficient information.
I didn't want the post to become too convoluted and too much to read.

More information:
I drive a 2009 Toyota Prius with 183k miles on the odometer. It burns about one quart every 5,000 miles. These cars are notorious for the piston control rings becoming clogged, resulting in some burning oil. I don't consider the amount of oil consumption too bad right now, but wondering if some of my more recent extended oil change intervals of about 12k miles with good quality oil may have played a factor in the reason it is now burning oil and has some varnish visible at the crankcase fill opening. I keep a good record of my oil changes, and I've only done these "long" (10k+) OCIs about 6 or 7 times. Average OCI over the life of the engine is 7k miles. Currently pondering whether to continue the extended OCI approach or adopt a shorter OCI plan of no more than 5k miles.
 
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A, but at 7,342.6 mile intervals. There's no reason to insist that either option has to cost nearly the same, it's a small drop in the TCO of a vehicle.
 
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I go with A.

But I'd change at 10k intervals. It's easier to remember cardinal numbers like 10k, 20k, 30k, etc. Who wants to remember 12k, 24k, 36k, blah blah.

Bottom line, I'd check owner's manual to see if going that long is allowed.
Who wants to remember three numbers when you can just do October or October and April? That comes the same time every year and yes they have nice days in both those months bet on it!
 
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Synthetic & Better Filter
Less Effort.

It goes without saying that both lubricants and filters have to be adequate for the service intervals you propose.

Actually I would likely do C.
B - 5000 mi = 5 qt Budget Blend + Filter w/ Nitrile ADBV
$15.15

C - 7500 mi = 5 qt Budget Synthetic + Filter w/ Silicone ADBV
$20.65

I haven't done the math but I suspect C is most cost effective.
 
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I'd like to know what members of the BITOG forum would choose for their vehicles. (Let's assume that cost is equal.)

A. 12,000 mile OCI with high-quality 100% synthetic oil (such as Amsoil signature series, which is rated at 25k miles) + very high quality filter.
B. 5,000 mile OCI with generic conventional oil + average quality (low cost) filter.
The choice totally depends on the engine in the vehicle, and driving habits.

Your question cannot be competently answered without that information.
 
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The answer is "it depends."

I'm perfectly comfortable with a 5,000 mile OCI with a typical SN conventional oil and a typical (eg WIX) filter on my Accord V6. But I would never have done that with my BMW.

The BMW oil monitor was okay with a 25,000 km (15,000 mile) OCI with a very good synthetic oil and a very good filter. But the shop foreman at the BMW dealer suggested I change the oil at half that interval to protect the valve train if I was going to keep the car for the long run. So that's what I did, but I did leave the filter for the full 25,000 km. So I wouldn't have been completely comfortable with option 1 for the BMW, unless there was a lot of highway driving, though the BMW manual and the oil monitor would have both said it was okay.
 
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