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0-20 vs 5-20

My car uses 0-20 which is syn oil. Manual says u can use 5-20 but should than try and use 0-20 at next oil change. So, it’s ok to drive 3-4k miles with 5-20? Is it also ok to use Dino 5-20 also? Of course all oil has the proper API rating of SN.

I’d stick with the recommended 0-20 synthetic. Why risk it?


Is there a specific reason you’re asking?
I agree with Texases, but cannot help but wonder why the question is being asked.

Owners manual is somewhat vague. It says u can use 5-20 oil. there might be words that say adding 5-20 is ok. Manual says check oil level, add oil if low. Use approved 0-20 oil but 5-20 is ok. 1 qt? 2 qts? 5 qts?

I would stick.with synthetic oil. It seems to be required in most new cars. I am not sure that 0W-20 or. 5W-20 would make much difference except in extremely cold climates. My 2011 Sienna calls for 0W–20, but 5W-20 synthetic may be used if 0W-20 is not available, but should be changed back to 0W-20 at the next oil change. However, in my area, 0W-20 is widely available and my local Rural King store has 0W-20 available for $2.69 a quart and it meets. Toyota specifications. I have had no oil consumption with 0W-20 in hot weather driving on long trips.

It seems that the manual wants you to use 5W-20 for just a short amount of time. Since this is the case…stick with 0W-20 and forget about using 5W-20.

What is the car, year and engine? I use the manufacturer’s recommended oil viscosity for my cars and in the absence of any other information, that is the right thing to do.

+1 to missileman’s post.

My 2012 Toyota Camry manual says you can use 5W20 if 0W20 is not available but change at 5000 miles instead of 10000. I presume the shorter interval is because 5W20 is available in dino oil.

0w-20 forces you to use 100% synthetic oil without the car maker (Toyota) expressly stating you must use synthetic. That’s why the 5w-20 alternative…It could be dino oil and that’s okay, but they don’t want you leaving it in there for 10,000 miles like you can with the 100% synthetic 0w-20 grade… And if you DO use 5w-20 dino oil for an oil change, they then REQUIRE you to use 0w-20 for the NEXT oil change, probably to (hopefully) remove any deposits the dino oil might have left behind…

There is probably more going on with the 0w-20 grade than just a slight viscosity difference at cold-start-up that safely allows 10,000 mile change intervals…if you change it every 5K miles, (the severe service schedule) then the more available and cheaper 5w-20 grade will probably due just fine…

Another little oil factoid…20 weight comes in two flavors…20W and just 20 with no “W”…This means that some grades and brands of 20 weight oil will flow at zero degrees F. and some will not…

“0W20 forces you to use 100% synthetic oil”

Not entirely true

We stock genuine Honda 0w20 synthetic BLEND oil in our fleet warehouse

I wouldn’t doubt that it’s a combination of Toyota not wanting complaints about increased fuel consumption with the slightly thicker oil and also being leery of dino oil possibly causing sludging. They have reason to be paranoid with sludging complaints in the past on some engines.

We stock genuine Honda 0w20 synthetic BLEND oil in our fleet warehouse

I’ve asked this before…and no one was able to give me a satisfactory answer.

Blend is a mixture of Synthetic and Conventional oil. To make the 0w-20 blend…where are they getting the Conventional from?

I trolled the web for an explanation of multi grade oils. This link explains it well:

Viscosity index modifiers are added to a 20 weight oil to provide increased lubricity at low temperatures. It’s still a 20 weight oil, but the paraffin molecules can’t collect as well at low temperatures; thus the increase in lubricity. While a 0W20 oil and a 5W20 oil have the same weight, the 0W20 provides increased lubrication at low temperatures until the engine warms up to about 200 degrees where the 20 weight is effective.

Given this, I can see making 0W20 synthetic oil blended with 20 weight mineral oil and still have acceptable 0W20 properties. If the manufacturer figured out a way to blend viscosity index improvers effectively with 20 weight mineral oil, I imagine they would sell 0W20 mineral oil too, and make a good living even at a lower price than synthetic.

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Viscosity index modifiers are added to a 20 weight oil to provide increased lubricity at low temperatures.

No…just the opposite. Modifiers are added to 0 weight so when the oil heats up it becomes as thick as 20 weight.

You don’t mix mono grade oils to make a multi grade oil. Multigrade oils are made by adding modifiers to a low viscosity base stock. As the engine/oil heats up the modifiers expand and thicken the oil to the desired higher weight. The wider the range the more modifiers and less oil.

AE Haas wrote the Motor Oil University section at BITOG. He says that multi grade mineral oils are based on the lower grade oil and viscosity enhancers creat the multi grade characteristics as you said. He says synthetic multi grade oils are based on the most viscous grade, not the least viscous one. He does not say how multiciscosity characteristics are created in synthetics, though.

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@jtsanders Multi-viscosity synthetics are created the same way as regular multi-viscosity oils. The synthetic part refers to the BASE STOCK, which has many additives added, including viscosity modifiers, giving you the 5W30, 5W40, and even 5W50, which is not possible with a regular mineral oil. The base oil would be a 5 viscosity in this case.

Modern motor oils have about 25% or more of their volume in various additives which gives them that long drain quality compared to oils of the 50s and early 60s.

Yes, that is what I understood to be the case, and what I thought I said.

It’s hard enough to find syn 0-20. I bet almost none carries 0-20 blend. WM does not stock generic oil these days. No profit? Or no shelf space.

If WalMart can make enough money selling name brand motor oil, then they won’t pay someone to bottle oil in a generic container. I recall seeing a name brand oil with a label that said it was bottled for WalMart.