Synthetic vs dino

Hello folks! Last Fall (2014) I posted about changing from dino to full synthetic and extending the mileage from 3000 to 5000. 15000 miles (3 oil changes) and 8 months later I have concluded that full synthetic is a good choice for me. I just changed my oil and filter at the 5000 mile interval and the oil color was honey brown, not black as before with dino. The performance is not something that I can notice, but I “believe” that I’m getting better MPG, it’s a Yaris rated at 32 overall, 35 highway. I get 48 MPG overall since my change over in October, however my commute is about 85% highway at 60 mph. I’m satisfied that the extended oil change doesn’t appear to be “hard” on the oil (color is by no means a scientific data result but still means something to me) and I’m happy to be doing less changes as I’m getting older. For 15000 miles I paid $60 for three 5 quart jugs of Pennzoil Platinum full synthetic, normally $22.99 at Wal-Mart on sale and then deduct the coupon for $3.00 from the Pennzoil website, or $20 per jug. My filters are Purolater at $2.99 also from Wally World, so my oil changes cost $ 69 for 3 changes @ 5000 miles each, total 15000 miles. Dino used to cost $18.00 per 5 quart jug, filters the same price, changing @ 3000 miles was 5 times in 15000 miles, or about $99.00 per 15000 miles. I will still have extra oil after each change (the Yaris uses 4 quarts at a change) so I’ll get a “free” oil change in both scenarios. Although the difference of $69.00 vs. $99.00 is considerable, it’s not the reason for the switch. I switched to lessen my time under the car. I’m getting older and laying on the ground isn’t fun anymore. The increase in MPG may be due to break-in, but my commute has not changed so I believe that my mileage went up from about 42 pre-synthetic to about 48 post synthetic. My conclusion is less work, cheaper, better mileage and good engine protection with synthetic. Happy motoring! Rocketman

The performance is not something that I can notice, but I "believe" that I'm getting better MPG, i

I know a guy that switched all his lubricating fluids to synthetic. After several months and meticulous records…he calculated his trucks mpg increased about .2mpg.

There have been several studies that have show that synthetic oil does NOT increase gas mileage.

Yeah Mike, that’s why I said “I believe”. The better MPG may be due to break-in, winter vs summer fuel, driving habits, traffic, whatever. But at least it didn’t drop, seems like it went up, so I’m pretty happy. Mostly happy about not doing as many oil changes, I’m driving more nowadays and I don’t like to skimp on maintenance. The 3000 mile maintenance was annoying, I can live with 5000 for now. Still looking for alternative, maybe going to 7500 with another product or multiple filter changes. Yes, I’m a PIA tinkerer. Rocketman

With 85% highway driving, I’d be at 7500 miles now, but that’s me.

@rocketman The 5000 mile interval is the normal interval for nearly all Toyotas. My 2008 Corolla gets changes at this interval, and after 5000 miles the oil is still clear and there is no oil consumption. In fact, after more than 8 years, I have yet to add any oil between changes.

There appears to be no difference between synthetic or regular mineral oil in the way the car behaves.

As others have stated, don’t change to synthetic to get better mileage or to stretch the interval way beyond what the manufacturer recommends!!!

Synthetic is better of course, especially if you have severe cold starts and very hot operating conditions. You will have less engine wear and longer life.

When I was 14 my Dad got me a job at the local Mopar dealership prepping new cars, minor mechanics and stuff through major stuff years later, I quit at 22 to go to grad school. That was 1971, we had lots of cool stuff to work on, used cars like Cudas and Road Runners were common. We serviced the State Police cruisers too, that was cool! I used to deliver a cruiser to the barracks all the time. I was a “floater” and worked at all stations, from oil changes through body shop, wherever I was needed. We always changed oil at 3000, hundreds of oil changes for me, so it’s a hard habit to break. But I’m adjusting . . . maybe I’ll go to 7500 Tex, we’ll see. Thanks for your responses! Rocketman

I can attest that switching my old mower from straight 30 weight to 10W 30 full synthetic really reduced the oil consumption.

The 5000 mile interval is the normal interval for nearly all Toyotas.

Oh I wish that were true. The NEW Toyota interval is 10,000 miles. I still change my oil every 5k miles.

Holy cow Mike! 10,000 miles? Just imagine what’s out there in the used car market these days with such extended maintenance intervals. Rocketman

I’d go with the recommended change interval from Toyota whether it is mineral oil or synthetic, even if the car is out of warranty. If that is 7500, then by all means, got to 7500 miles. I’ve driven mostly highway miles for my commute in an Accord V6, and i change oil between 7000 and 7500 miles. After 142,000 miles, I use no oil between changes.

I Use Mobil-1 Extended Performance And Change At 5,000 Miles.
If You Haven’t Already Used Blackstone Labs, Why Not Give Them A Try? I Did When I Wanted to See The Value Of The OLM On My Wife’s Car. Also, Since The Car Was A Certified Used Car I Wanted To Check The Engine Health As A Baseline.

You could send a sample from a 5,000 mile change, 7,500 mile change, or both. They have a space for personal comments and questions and they will respond with your results. They were pretty speedy when I sent a sample.

They sent sample bottles free of charge when I called. Their Standard Analysis is $25.
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I just changed my oil and filter at the 5000 mile interval and the oil color was honey brown, not black as before with dino.

Just curious, still using dino and any oil change on spec is a good oil change, but why would synthetec be cleaner than dino,

2 possible conclusions in my book.

1 dino oil causes dirt

2 synthetic does not trap dirt as well as dino oil.

Willing to learn something new everyday.

I normally use dino oil (5000 miles in ~ 9 months).
The one time I tried synthetic it looked a little darker.
File it under YMMV, I guess.

That’s a great summary Rocketman. Thanks for the update.

And thanks for letting us know about the Pennzoil $3 coupon you found. I’ll check their website before buying oil next time.

@Barkydog - synthetic and dino don’t have any basic difference in dirt holding. Synthetic can perform better viscosity-wise at extreme temps. There is Mobil1 Extended Performance, guaranteed for 15k or 1 year intervals, if no severe service and out of factory warranty, must have extra components to suspend dirt. I wouldn’t extend change intervals beyond factory recommendations, but I sure would be comfortable following the factory recommendations.

@texases ,

Didn’t Mobil 1 have a problem where their synthetic av oil wasn’t holding TEL byproducts in suspension well enough?

I don’t know that you can generalize that to ALL synthetics do a worse job of holding ALL contaminants in suspension in ALL uses…but I don’t know that you can’t, either!

Sometimes the synthetic will resist breakdown a little better,there used to be a commercial(fwiw)that showed regular oil turning to gunk long before synthetic when exposed to high temps,originally synthetic was developed for use in arctic conditions and I suppose the better chemistry gives you a bit better control of the molecular behaviour at temperature extremes.
I know you shouldnt do this,but I used to feel the oil as it was draining out and also watched the color,some oils felt full bodied and slippery at the cycle end and some brands felt about as slick as water.I have always had good luck wjth synthetic,but sort of figured the perceived mileage boost was largely imagined
The same way with regular gas,sometimes the pure gas gives a bit better mileage and sometimes I cant tell the difference some of my cronies claim fantastic gains running straight gas over E10,I,m not buying it if the vehicle was optimized to take advantage of the higher octane of the ethanol there should be very little difference(icant believe 2-3 mpg on a gas guzzler) Guess what Folks,low sulfur gasoline is on the way(what next?)

I agree with commonsenseanswer who suggested basing your oil changes on an oil analysis. I suspect that you could very easily extend your oil changes to 7,500 miles or even more, simply based on all the highway miles you drive, which don’t beat up oil as badly as stop n’ go and repeated heating/cooling cycles does.

The problem with oil analysis is people THINK that the analysis they did 5 years ago is relevant today. It’s NOT. After years and miles of use the parameters change. So you have to keep doing them…thus making them cost inefficient.

We’ve had the discussion before. I use Mobil 1 in my Acura that calls for 0-20, Mobil 1 5-30 in all my small engines, and dino in two other cars. I do not extend the oil change period at all using the Mobil 1 and because it is so popular an idea would hesitate to buy a used car where the owner used synthetic unless I knew what the change intervals were.