No, this change was first driven by fuel economy requirements and second, logistics. They back-spec'd different models as far back as 2003 (for some) to indicate that 0W-20 was acceptable to use in them. Why ? So dealers could buy MORE 0W-20 in bulk and have to stock fewer viscosities.
2012 Civic R18Z1 engine oil weight
- Thread starter Nac Mac Feegle
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I've also read somewhere that they got some sort of federal credit for back-specing. Any truth to that?
Again it wouldn’t make a difference.
I think CAFE or EPA only care about "current" model year units (vehicles). It's a year-by-year system. The EPA would have to go back and re-test previous year models. That's not going to happen.... IMO, in Honda's case, they did this for their own reasons (logistics, inventory, etc).
We had a long thread about this a while back, and the EPA does allow for retroactive credit for a certain number of prior years with proper documentation. The ability of lower viscosity oils to decrease fuel consumption is not the question, it was whether such oils would be detrimental to engine longevity. Back in the days when a 20-grade oil was the grade under consideration it was pretty established that most engines would not incur excessive wear using that grade. But these days with ILSAC GF-7B that may not be the case so there may be little if any instances of "back specifying" as it is called on here.
Switch to Restore and Protect and see what happens to your consumption. 5w-30 is perfectly fine and preferable.
There's no reason to assume Honda would make running design changes to an engine. They've been making engines a LONG time and they have the tools to get it right the first time.
It seems likely to me that oil viscosity changes are almost never a response to engine design changes but rather a way to avoid design changes. See GM switching from 20 grade to 40 grade.
I'll take your word for it.... I'm curious what sort of documentation would suffice though. I mean, Honda could argue that it's the same engine, same chassis, etc and switching from 5W-30 to 0W-20 increases fuel consumption by 0.037%, but in Honda's case, they went back a decade or more. They didn't do that for EPA compliance.
Exactly - if it ain't broke, don't fix it.
Japanese
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Yes, but back in 2012 that car was new and the previous model was spec'd to 5W-30, afak. He's asking for back in the days, not retrospective EPA approval.
Also, some 10 or more years ago there was tendency for 5W-30 to don't lubricate well timing chains vs 0W-20 which was doing better job.
Hence, the new API specs SP and SQ mention optimal timing chain lubrication but I don't think we can say the same about the API SM and SN oils back in the days. I think the lower amount of moly and ZDDP of the API SM/SN oils didn't do well with timing chains, but not sure.
Many engines in the late 2000 became timing chain driven when most of the 80s and 90s engines are timing belt driven. The individual timing chain links along with the timing chain tensioners need to be not only lubricated but clean as well. In that case Valvoline R&P, Mobil 1 Euro 0W oils and Castrol EDGE Euro 0W oils along with HPL, Amsoil, Red Line oils—all do excellent job.
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Topic did go off on a tangent, but this was strictly in reference to fuel economy.
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This actually refers to a different car, a 2006 Camry which is currently being run on Total Quarts Long Life 5W-30. The Civic has 52K on it and I haven't had it long enough to measure its consumption.
This is one if the points that I was hoping to clarify, and the 2AZFE in the Camry was an example of a manufacturer changing an aspect of the design without changing the engine designation (not that I am aware of, anyway). Subaru did this too, with the Phase 1 EJ22E making numerous tweaks small and large, including a completely different head casting (single and two exhaust ports).
Certainly seems possible
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I think that the previous R series civic engines were 5W-20. The D series, of which I've had four (D16Y7 and D16Y8's) were definitely 5W-30 (and had belts, to your point below)
Good point. The Total Quartz that the Toyota has been running is an SN rated oil. Question: Why would you name a lubricant after a notoriously hard mineral?
Interesting point and worth consideration.
It’s because physics hasn’t changed. People can make all sorts of speculative propositions but in the end, physics is still applicable.
Japanese
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What is you location? Why do you use Total Quartz? Also, what viscosity and which one—Quartz 7000 or 9000?
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Coastal mid Atlantic.
Advance Auto clearance at $2/quart.
Total Quartz Ineo Long Life 5W-30.
Endorsements are:
API SN
ACEA A5/B5
MB 229.51
VW 504.00
VW 507.00
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I agree - Physics are physics. And as long as clearances didn't change then the older spec is applicable.
Clearances haven’t changed really for years. The way manufacturers have compensated for GF-7B oils is mainly through bearing width and coatings, plus some additive changes. But not clearances.
It’s back to the basics of why higher viscosity oils are still fine even in engines that tolerate 8-grade oils. It’s not about clearances, and it’s why modern engines still don’t self-destruct when the oil is at any temperature other than normal operation. The relative difference between an 8-grade and a 40-grade at operation is nothing like any grade when cool or cold.
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