0W20 Myth or Truth

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I head somewhere that all the Honda's, Toyota's, + Some other vehicles that were initially spec'd for 5w20 can safely move to 0w20. Some dealerships even recommend it.

I recently moved to a full synthetic high mileage 0w20 in my 05' Odyssey which originally calls for 5w20 and has been running great and not burning any at all.

Thoughts?
 
I guess that if the Mfg has now allowed a different weight oil, you'll be fine. I am more interested in vehicles that spec ONLY 0W20 but can I run 5W20 or 5W30 conventional or synthetic. Only because I want to use up some stash on hand.
 
The only possible exception I can think of is if you have a turbocharger and are running low-end or middle-of-the-road ILSAC oils. The GF-5 spec requires all grades except 0W-20 to achieve certain results on the TEOST 33C test, which estimates turbocharger deposits. So, a GF-5 5W-20 would carry that measure of assurance, whereas a GF-5 0W-20 wouldn't.

However, I wouldn't be too concerned about that with a high-end synthetic 0W-20.

In all other cases, I'd imagine 0W-20 would be completely acceptable (if not better) as a substitute for 5W-20.
 
Originally Posted By: jayjr1105
I head somewhere that all the Honda's, Toyota's, + Some other vehicles that were initially spec'd for 5w20 can safely move to 0w20. Some dealerships even recommend it.

I recently moved to a full synthetic high mileage 0w20 in my 05' Odyssey which originally calls for 5w20 and has been running great and not burning any at all.

Thoughts?

Well both 0W-20 and 5W-20 are 20-grade oils, one would not expect you to burn more of the 0W-20 since both are the same weight. In order to achieve the 0W cold-cranking and pumpability specification it sometimes requires a better base stock so for the most part those oils are superior.

0W-XX oil is not thinner than a 5W-XX or 10W-XX counterpart except at extremely low temperatures, and even then only marginally so (while being extremely thick at that temperature compared to operating temp).
 
Originally Posted By: kschachn
Originally Posted By: jayjr1105
I head somewhere that all the Honda's, Toyota's, + Some other vehicles that were initially spec'd for 5w20 can safely move to 0w20. Some dealerships even recommend it.

I recently moved to a full synthetic high mileage 0w20 in my 05' Odyssey which originally calls for 5w20 and has been running great and not burning any at all.

Thoughts?


Well both 0W-20 and 5W-20 are 20-grade oils, one would not expect you to burn more of the 0W-20 since both are the same weight. In order to achieve the 0W cold-cranking and pumpability specification it sometimes requires a better base stock so for the most part those oils are superior.


I thought to achieve a higher viscosity spread you need to add more viscosity improvers which makes the oil susceptible to shear?
 
Originally Posted By: camrydriver111
I thought to achieve a higher viscosity spread you need to add more viscosity improvers which makes the oil susceptible to shear?

Not always, it is also dependent on the base stock.
 
Originally Posted By: camrydriver111
Originally Posted By: kschachn
Originally Posted By: jayjr1105
I head somewhere that all the Honda's, Toyota's, + Some other vehicles that were initially spec'd for 5w20 can safely move to 0w20. Some dealerships even recommend it.

I recently moved to a full synthetic high mileage 0w20 in my 05' Odyssey which originally calls for 5w20 and has been running great and not burning any at all.

Thoughts?


Well both 0W-20 and 5W-20 are 20-grade oils, one would not expect you to burn more of the 0W-20 since both are the same weight. In order to achieve the 0W cold-cranking and pumpability specification it sometimes requires a better base stock so for the most part those oils are superior.


I thought to achieve a higher viscosity spread you need to add more viscosity improvers which makes the oil susceptible to shear?


Yes, only if you use the same base stock as the 5w20 oil.

All top shelf 0w20 oils use better base stock with higher natural VI so there is no need to add additional VII over a 5w20 formula.
 
Also it is quite possible for a 0W oil to have a higher viscosity than a similar 5W or 10W oil except at very low temperatures.
 
Conventional wisdom says run the grade specced and printed on the oil cap as long as the vehicle is under warranty, though that's not likely to apply to an '05. It also says that unless you live in northern Maine or Minnesota, 0w will provide no real benefit over 5w.

With that said....I use whatever 0w-30 or 5w-30 synthetic is on sale and/or rebate. For that matter, I would run 5w-20 in winter without hesitation. (My Corolla is back-specced to 5w-20 though shops do not believe that since it's not in their computer.)

For normal driving and OCIs, today's synthetics or even SN/GF5 semi-synthetics let you sleep well at night, knowing your engine is protected. If you take your car to the track---not likely with an Odyssey, I reckon---or pack it past the load limit and drive to the mountains every weekend, or live in rural Minnesota and park outside, then your needs might be different.

If your vehicle starts to burn oil when you switch from 5w-20 to 0w-20 it's more likely the new brand of oil than it is the switch from 5 to 0.

Rest easy and enjoy the ride.
 
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Ive used it all on my car. My car is back spec'd but ive used 0w20, 5w30, 0w40, 5w50 and no issues..well 5w50 slowed my engine down and drank gas. The rest were no issues. 0w20 runs flawlessly. Id put 0w20 in any car spec'd for 5w20.
 
Originally Posted By: Rolla07
Ive used it all on my car. My car is back spec'd but ive used 0w20, 5w30, 0w40, 5w50 and no issues..well 5w50 slowed my engine down and drank gas. The rest were no issues. 0w20 runs flawlessly. Id put 0w20 in any car spec'd for 5w20.


Why would you stray as far as 5w50. I'm no expert but that seems not smart in a corolla.

Thanks everyone for replies. I'll use 5w20 or 0w20 HM, whatever I find on sale. Hot summer and the van seems to be doing great with full syn 0w20 though.
 
0w20 is an easy way to mandate customer running a synthetic. At least I haven't seen any suspicious label junk in gas station or dollar store in 0w20 grade.
 
Originally Posted By: jayjr1105
I head somewhere that all the Honda's, Toyota's, + Some other vehicles that were initially spec'd for 5w20 can safely move to 0w20. Some dealerships even recommend it.

I recently moved to a full synthetic high mileage 0w20 in my 05' Odyssey which originally calls for 5w20 and has been running great and not burning any at all.

Thoughts?


0W has nothing to do with operating oil weight or viscosity.


note: its seems the asian market 0w tend to be thinner (near the now 0w16 KV100 but not HTHS)

Idemitsu was low 7cst out of the box and into the mid 6's after a months service. Thin stuff


Wife and I loved the Valvoline 0w20 in our Forester. Best performance out of the top oils tried rating: cleanliness**, stay in grade and lowered engine racket.


** just subjective visual of the top of the VVT mechanism as seen through the large oil fill neck.

Some of the top oils showed hard brown varnishing. Valvoline was pristine clean at the end of the OCI.
 
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If I lived in Canada a 0W anything would be a no brainer, whether a 0W 16, 0W20 or 0W30. When I lived in Virginia I ran a 0W30 year round in my Camry which at the time was specked for a 10W30
 
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