Synthetic oil

How does full synthetic oil compare $$ to regular dino, let’s pretend both are are on sale at Wal-Mart. Double? Triple? Worth the extra money? How much more do you extend your oil change interval? If you change dino at 3000 would you take the synthetic to 6000? Thanks! Rocketman

I use synthetic in my air cooled motorcycle and dino oil in my car. I change the oil at normal intervals. I don’t treat synthetic motorcycle like long life oil, because they are two different products.

Wally Dino is $3? Their syn is $4.25? Pretty close. If u need 0-20 u r forced to use syn. There is a good amount of Dino 5-20 out there. Pretty common. Once u get into 30w stuff, it’s easy to find both types

I’ve never bought into the synthetic hype so I only use synthetic if my vehicle requires it. If you switch to synthetic you cannot increase the oil change frequency so I don’t bother. In theory…it’s a better oil than dino but not by much. For that reason it’s just not worth the extra money.

My fiance’s step dad was a mechanic for a long time. He uses synthetic and doesn’t change it for like 6-8000 miles. This is compounded by the fact that he hates to work on cars anymore, lets the dealer do it, let’s the cars computer tell him when, and the car holds about 7 or 8 quarts I think so it’s pricey. He also doesn’t think you should change spark plugs unless there’s a problem. (150k on original plugs on one of his cars).

I completely disagree. Spend a little extra money on more frequent oil changes (3-4k intervals) using regular. And change the spark plugs once every couple years is my own method. It’s cheap engine insurance and I enjoy keeping them going. He on the other hand says I’m tossing my money out the window when I do most preventative maintenance practices. But hey, he has money to update his car every 4 years or so. Mine need to last about 10 at least!


Your fiance’s step dad is doing things that are at complete odds to his mechanic background

Maybe he’s just gotten lazy

Hopefully his practices don’t come back to bite him in the butt

Changing the oil on regular basis with correct spec is most important. The rest of it including brand and type(conv vs synthetic) is akin to different varieties of spring water vs tap water. They all do the same thing.

I agree, a mechanic that doesn’t believe in preventive maintenance, does extended oil changes, etc. I dunno, maybe he has a drinking problem or something.

I buy my oil at the farm store not Walmart but the best way to compare prices is to check the shelf. Regular Mobil is about $4 and Mobil 1 is about $7. You do not extend oil changes with syn, but we’ve had that discussion before. I’m thinking of changing my small engines over to syn now that Briggs changed their recommendations but still use dino in two cars and syn in the other.

Let’s not denigrate synthetic oil too much, there are varieies of synthetic oil that are designed for extended use, and they have their place. There is also the fact that synthetic oil holds up to excessive heat better than dyno oil.

“The rest of it including brand and type(conv vs synthetic) is akin to different varieties of spring water vs tap water. They all do the same thing.”


If your car calls for 0w40 full synthetic and 10k oil change intervals . . . and you use 5w30 conventional, but stick to the 10k oil change intervals, you may run into trouble

Maybe a botched oil change kills an engine faster than what brand of oil you use. I have only lost an engine due to having none of either kind of oil in it. The idiot light was disconnected and the oil was leaking through the sensor. On a 350 engine in a 76 Impala I might have at least tried to find the oil leak. Oh well $350 later I was driving again with a used engine. Do whatever you like, I’ll bet a dollar that the engine will never notice.

Synthetic oil has unique advantages of start up lubrication where much of the wear occurs. It is more stable on the upper end, acts as a better engine coolant if you tow and use your car hard, especially with extended idling. Extending your change interval is practical in many situations but, IMO, not if you aren’t a high mileage driver or own an older car. I am putting fewer then 10k miles on one of my vehicles which was not designed with synthetic in mind and see no advantage in doing it and would not recommend it for others in a similar situation.

Now, if you put 20k per year on a newer car, you would be a fool not to take advantage of the extended oil change intervals, as high as10k. It was routine in the state vehicles and payed huge dividends over time. I use it in my tractor, both generators, outboards etc. and the car with synthetic definitely turns over easier in the winter. One thing is for sure, there is no advantage to recommending extended oil changes for the manufacturer other then milking more money out of you…how ?

True story. I took my car in for a 5 k oil change even though it was running synthetic. Since I bought it used, I assume that I did not know how it previously was used. My plan is to slowly extend it to 7500 and then once a year. The dealer gave me this option: I could pay them $45 for a synthetic oil change ( less then $10 more then a regular) or, not do the oil change at this time but do fluid top offs and rotate the tires for $80…doing the the oil change at the next interval. So I said to the writer. “You want me to pay you $30 more for doing less ? I’ll just rotate my own tires, which I have to for the winter change over in my garage anyway, open the hood and look at the fluid reservoir and have you change the oil and save $30. " I wonder how many fall for this ? He said"well, we can’t check your brakes without taking your wheels off.” I replied, “they are fine. I stopped before running into to you when you came out to greet me.”

I wondered how they could do less work for more money with synthetic. Now we know…the old Texas side step. Now you see me now you don’t.

We have this same exact debate on synthetic vs. dino, from time to time. And, the same (often wrong) information gets posted by the same posters.

OP, if you want to know what is correct, try dino and syn, on your car, if this doesn’t violate warranty rules, at the mileage you think is correct, and send a sample of each to Blackstone Oil labs and find out what the truth is. Otherwise you are guessing, or trying to sort out postings by others who are guessing, by guessing who is correct.

Several years ago, after years of these debates, I decided to find out for myself. I use Mobil-1 EP and drive outside the snow zone, at that time almost always highway driving. I let it go to 8800 miles and then sent a sample to Blackstone. All parameters, and Blackstone checks a lot of them, showed the oil was still good for at least the full 10,000 miles, period. Note the car was already high mileage when this happened. And, also note I did not change the filter, as many recommend. But, particulates were normal.

With a worse motor, or different driving conditions, your oil life may be different. And, of course, newer motors which use synthetic 0W-20/30, are not recommended to go as long as my 10W-30 EP is. I think they recommend 5,000 miles for that oil. Ditto on oil testing if you use this oil. Modest cost to eliminate guessing.

If you live in the snow zone, you obviously should test it twice; once in summer and once in winter.

First, you can indeed extend oil change life with syn, as long as during warranty, you stay within manufacturers requirements. Once warranty is gone, you need only do what is best for your motor. My car was required oil change very 7500 miles, so my 8800 miles was greater. But, that only proves the 7500 change recommend was not outrageous.

Since my lifestyle has changed in my 70’s, that is, I no longer take long trips across the US, so my car gets around 5,000 miles a year here in Mexico. I change it that once a year when I go back to the States.

Second, there are indeed benefits from syn on ordinary cars with ordinary driving. Syn does reduce wear; this has been reported over many years by many researchers. Also, when I did my oil testing, I searched for sludging. Universally, all experts said to use synthetic oil on cars which tend to sludge. That alone makes syn well worth it in ordinary driving.

Let me add another note on oil testing. It doesn’t just supply information on your oil’s condition. If you read the report in depth, it tells you a lot about the condition of your motor. It’s like having a microscopic mechanic crawling through your motor and reporting on everything. Bearing or valve train wear shows up in metal contamination. Ditto for coolant contamination. You can’t get a mechanic to inspect your motor’s condition for the price of an oil test, and no mechanic can tell as much about your motor as an oil test.

Another bogus argument is, it’s cheaper to change the oil than test it. True, but changing the oil gives you no information on engine condition. Send in a sample when you change it for that information, and it’s still a bargain.

Once in a while, someone will say, “If you care about your car, you will (fill in the blank.)” I will say if you really care about your car, you will test your oil and see what your car needs, heh, heh.

I really don’t care what you do, dino or syn, 2000 mile changes or 10,000 mile changes. What I do object to is those who are guessing and trying to push their choice on others as correct.

Ultimately, to each his own. Its good that we’re all debating on the best methods for the highest longevity of the engine. I find the oil testing interesting, but at the same time, if they are finding tiny traces of metal or coolant in the engine am I going to tear it apart and rebuild it? No. I’ll watch and listen carefully until the problem is significant enough to diagnose the source. Some synthetic guys just like it because they have to change the oil less and feel like they’re saving money. For me I enjoy changing my own oil, and I do personally do it every 3000. Its cheap insurance. Why risk things and over analyze it? That oil very well may have an additional 2000 miles of usable life in it when I drain it, but I’m not taking the risk just to set back a $25 maintenance item another month or two. I think I just like turning a wrench on my vehicles and feel better when they’re freshened up. But again, to each his own.

If your goal is to keep the engine for a long time, change the oil per the manufacturer’s recommended schedule (or more often) using the oil recommended in your owner’s manual and keep the oil’s level filled.

If your goal is to go as long as possible between oil changes and you’re willing to risk engine damage to do so, then go ahead and extend the length between changes based on what type of oil you’re using. If the stuff under your valvecovers begins to look like roofing tar, well, it was your choice.

Me, I’ll choose option 1.

Comparing one car going 10,000 miles between oil changes to another car doing the same is talking about apples and oranges.

A 2003 Ford Taurus with a 3.0 liter engine holds 5 quarts of oil and uses a plain old oil filter.

A 2003 BMW with a 3.0 liter engine holds 8 quarts of oil and uses a filter that costs 3 times as much and is significantly larger.

Simply having a filter with twice as much filtering media and an oil capacity 60% greater means better filtration and more oil to cool the engine and keep contaminants in suspension. Hence the oil should last longer between changes.

Then add the difference between synthetic and dino oils.

I’ve always believed in just following the manufacturer’s recommendation. Why second guess the design team?

Exactly. I always get a kick out of the people who think they know better than the hundreds (thousands?) on the team that designed, engineered, and built their car.

"I always get a kick out of the people who think they know better than the hundreds (thousands?) on the team that designed, engineered, and built their car. "

There might be some Chevy (timing chain failures) and Toyota (sludged engines) owners who would argue with that.

As I understand it, most of the Toyota sludge victims were their own worst enemies

They didn’t change their oil on time, or they didn’t change it at all

There were exceptions, of course, but many of the sludge victims should point their fingers right back at themselves