Mix 5W-30 and 0W-20

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Might be a silly question. Realized I have about 2.5 quarts of unused 5W-30 left over from the wife's late oil-burning Equinox. Thinking the Pilot will be the next one due for an oil change. I'm sure it would be fine, but any problem using up the 5W-30 and using 0W-20 for the rest?
 
Or you can just order 2 quarts from Walmart.com - ST and QS are both $5.xx/qt. Pilot only takes 4.5 qt, so you only need 2.
 
Doesn't matter what brand they are or if one is pure group 2 conventional and the other is pure group 4 or if one is 0w-8 and the other is 20w-50. People worry too much. Throw it in. I put 0w-20 and 15w-40 into my 2021 escalade. It didn't commit bad politician punishment when i started it right after.
 
Yes, the leftover 5W-30 is Pennzoil full synthetic (not Platinum). The Ram and the Pilot both call for 0W-20, and thankfully oil consumption seems to be undetectable on both. Probably makes makes sense just to pick up a couple quarts of 5W-30 since the J35 called for 5W-30 a while back.
 
Might be a silly question. Realized I have about 2.5 quarts of unused 5W-30 left over from the wife's late oil-burning Equinox. Thinking the Pilot will be the next one due for an oil change. I'm sure it would be fine, but any problem using up the 5W-30 and using 0W-20 for the rest?
I have 4 Honda Odysseys with the J35 V-6 with VCM enabled, all speced for 5W-20. I switched all of them over to 5W-30 permanently and engines seem to run quieter. No difference at all in gas mileage. Getting 27.5 consistently on flat highways with the 5W-30.

I made the permanent switch to 5W-30 after googling HTHS wear graph. Since my vans sometimes are fully loaded with 8 passengers, heavy luggage, and go on long trips up long inclines where engine temps rise, I feel the higher HTHS gives added wear protection for severe situations.

Mixing 0W-20 and 5W-30 shouldn't be a problem. When I switched to 5W-30, I still had about 2 quarts of 5W-20 left, and I mixed them with the 5W-30 with no ill affects for the entire oil change interval.
 
Well, I’m about to do the same thing...I have 3 quarts of 5W30 Amalie synthetic, and 3 quarts of Amalie 5W20 synthetic. Car takes 6 quarts. I figure...I’ll end up with a 5W25, or something. Wouldn’t all the heat exchanges, a crankshaft spinning at 2,000 rpm’s for hours a day, sort of “mix/blend” oil together? Ideally I’d just throw 6 quarts of Mobil1 EP in it, but I have this stuff laying around and want to use it up. But I may change my mind.
 
I have 4 Honda Odysseys with the J35 V-6 with VCM enabled, all speced for 5W-20. I switched all of them over to 5W-30 permanently and engines seem to run quieter. No difference at all in gas mileage. Getting 27.5 consistently on flat highways with the 5W-30.

I made the permanent switch to 5W-30 after googling HTHS wear graph. Since my vans sometimes are fully loaded with 8 passengers, heavy luggage, and go on long trips up long inclines where engine temps rise, I feel the higher HTHS gives added wear protection for severe situations.

Mixing 0W-20 and 5W-30 shouldn't be a problem. When I switched to 5W-30, I still had about 2 quarts of 5W-20 left, and I mixed them with the 5W-30 with no ill affects for the entire oil change interval.
Yeah, I did the same thing in my Toyota...once I reached 120,000ish miles, I switch from 0W20 to 5W30, because if the same HTHS graph.

Although I’m straying a bit with my next oil change...blending 5W20 and 5W30 together
 
I read an article on a reputable website (iirc, Machinery Lubrication but not %100 sure) that said it's not recommended to mix significant amounts of different oils since each oil can be formulated differently i.e. having different or incompatible or competing ad packs, base stock, etc.

Basically it was saying that mixing won't blow up your engine but the mixture may lose some effectiveness ...

At a minimum, it messes with the W rating of the oil based on what I recall @Shannow was saying in old days.

The leftover oil after an oil change, does not count as a mix since the amount is not considered to be "significant".

Anyways, true or not, the article caught my attention for a few seconds but it went off my radar and I didn't do further research since with my new(er) cars I never mix (only change oil and they don't burn oil) and with my older cars I don't care but I still use the same oil if I have to add. Just a habit.

I am just passing on the info. I'm sure you can find other articles that says it's ok to mix.

If I have a good chunk to mix, I use it in my old cars.
 
The chances of any negligible effects is so low that isn't worth worrying over. Mix it.
 
This thread is confusing. On the one hand we have companies like HPL who very carefully crafts their oil products, getting the exact ratios of all their ingredients to make the perfect formula. And this product is highly recommended.

Then you get people who say you can just mix whatever you want.

I would not do it, unless the two oils are from the same exact same brand and formula. So I might mix HPL 0w-30 with 5w-30 if they're both the Euro no vii formula, but I wouldn't mix 0w-30 PP PCMO with 5w-30 euro no vii even though they're both HPL. Completely different formulas.

For a start the PP is heavily magnesium based, and the euro no vii is calcium based. HPL carefully (I'm assuming) chose their ratios of calcium to magnesium for a reason, so mixing those together destroys those ratios.
 
Its not rocket science and one example for you:
My Toyota recommends a 10k interval with 0w20. The same engine, a few years older, recommends a 5k interval with conventional 5w30.

So, why did I ask this?
It's possible Toyota wanted to avoid some CAFE fines so they went to 0W-20. If not for CAFE, I would expect most cars in the US would be speced for 5W-30 in winter and 5W-40 in summer (Like Europe and Australia are) with the same engines as the cars in the US.

I just wanted to share my maintenance strategy designed so I can take each of my vehicles to 300k miles.

Oil: Lowest priced full synthetic 5W-30 with HTHS > 3.0.
Oil Filter: High efficiency rated at least 95%+ @ 20 microns (Ex: Fram Extra Guard for $3.50 if purchased on Amazon subscribe and save).
Oil Change interval (to avoid sludge/varnish/gummed up piston rings): 4k OCI / 6 months which ever comes first.
Transmission fluid drain and fill: 15k/3 years which ever comes first.
PCV Valve and tube: Every 30k miles.
Engine flushes: If buying a used car, I'll do an engine flush during the first few oil changes to clean out the engine.
 
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