Synthetic vs.regular oil - questions

Hi all, I am the owner of my sister’s 2018 Honda Civic. It is due for an oil change. The owner’s manual recommends Honda Genuine Oil, 0W20 detergent grade with API Certification. The manual says that “synthetic can also be used” provided it is the correct grade and API Certified.

Synthetic oil of the correct weight was used for the last oil change. Since synthetic oil is more expensive, it will help to know if it is also cost-effective. I need to keep costs down while maintaining the car properly to extend its life. Questions:

Can the synthetic oil go longer between changes?
Does the 6 month rule for frequency of oil changes apply apply to synthetic oil when driving under stress conditions? I will be mostly driving it on short trips in town in the Texas heat, with infrequent long trips.
If the oil needs to be changed every 6 months, is there a problem switching from synthetic back to regular oil?
Is synthetic better for the car in the long run?

Thank you for sharing your expertise!

yes to all.
if you are doing the oil changes yourself you can go to walmart and get it. synthetic is usually only a few dollars more . especially if its on sale, maybe the same price. its worth using synthetic.

Why are you questioning that ? Doesn’t the 2018 Civic tell you the oil condition ? Some vehicles read out something 25 % left which is a good time for an oil change .

Honda 0W20 motor oil is synthetic blend. Other brands of 0W20 are synthetic oil. Your oil change will be done with synthetic motor oil.

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You can use a full synthetic 0W-20, no need to use Honda brand oil. That’s what I’d do.

You won’t find any conventional oil in 0W20 grade. You will find either synthetic blend or full synthetic. The shop I work at uses full synthetic, as there is virtually no price difference between a blend and full synthetic.

The difference in cost between conventional or full synthetic oil change is negligible.

Great information! I had thought synthetic was much more expensive, but apparently the price has dropped. Thanks!

Synthetic oil is more expensive. But in this case the 0W-20 oil IS synthetic. There is no conventional oil in that weight. Honda doesn’t make oil. It’s made for them by one of the oil manufacturers. Every 5-10 years they renegotiate with oil companies for a contract. They’ve used Quaker State, Mobil and Castrol in the past. Not sure who their supplier is now.

Stick with any brand name oil that meets the same API and weigh spec.

I don’t believe synthetic blend is available in 0W20 either, only full synthetic. BTW, I read somewhere that “synthetic blend” oil is only about 1/8 synthetic, which sounds like a marketing gimmick. My Corolla gets full synthetic.

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I have seen 0w20 in synthetic blends, but why buy it, the full synthetic can be bought for about the same price. The most I have ever paid for 5a5 quart jug is less than $23.

It’s available…but I’m not sure how they make it.

USA - Motorcraft - SAE 0W-20 Synthetic Blend Motor Oil

And there’s more (at Walmart):

the way I understand it is 0W20 is full synthetic. You can’t get 0W20 conventional I believe. Like others said, go to WMT for synthetic oil. Super Tech is either 16 bucks for 10K or 18 for 20K (but don’t go that long between changes with that stuff), QS is about 20, pennzoil is about 22 to 24, mobile is 24 to 27, Valvoline is 21 or 22. Don’t go to auotzone/advanced auto or o reilly’s. They are way more expensive.

if you can’t find 0W20 in conventional (I know that like others said), then the blend has to be a different weight and it’s not 0W20 anymore (if you put 5W20 conventional to make a blend).

0W20 is available as full synthetic or (rarely) as a blend (see above).

If this vehicle is still under the powertrain warranty, then you still need to abide by the maintenance schedule regardless of oil type (conventional, semi-synthetic, or full synthetic). In theory synthetic oil could last longer, but you’d still want to follow the schedule regardless

Yes , 6 months or whatever mileage is specified, whichever happens first.

The particular grade your car calls for is going to be semi-synthetic or fully synthetic regardless. But you can switch between oil types without issue.

For the most part, yes.

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If keeping the costs as low as possible, and that includes maintaining the engine for the longest cost effective life, You could go to Costco and get their Kirkland brand oil in 0w20 synthetic at about $26 for two 5qt bottles, that’s only $2.60/qt. I think Walmart is carrying something similar in box of two 5qt bottles of Supertech.

Buy Honda filters from Amazon. Make sure they are the filter for your newer Honda as older filters had a different bypass pressure valve built into them. The newer filters need a lower bypass pressure to insure that the pressure sent to the engine is adequate for the lower viscosity oil.

The stick to the maintenance schedule in your owners manual and the instrument panel advisors. Do this and you will be well sick of that Honda before you have any engine trouble. Follow the maintenance schedule for the rest of the vehicle and you could have an antique on your hands before it is worn out.

Just following Honda’s oil spec and interval recommendation makes sense to me. They designed the vehicle after all. Is Honda’s oil significantly more expensive than other brands? Same for the filter, as long as the price is nearly the same, just use a Honda filter.

Whichever oil brand you decide on, stick with it. Each oil manufacturer uses a slightly different additive mix and they may not be 100% compatible. Don’t extend the oil and filter change interval just b/c you may be using synthetic oil.

That used to be an problem. No longer.

they’d have to add conventional 5w20 or just 20W oil with 0W20 synthetic. I’d go full synthetic. A couple of bucks more and no conventional to break down sooner than synthetic.