Using 5w30 in a engine speced for 0w20?

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What are your thoughts on using a quality synthetic 5w30 in a car like a new V6 Honda Accord that calls for 0w20? Wondering if the engine would be better protected with the 5w30. Thanks for any input!
 
Originally Posted By: hardcore302
if you dont live in the sahara i would just follow the manual

+1
There's more than enough evidence accumulated over the past decade to show Xw-20 weights offer all the protection needed in engines calling for it, along with engines back speced for it that originally called for Xw-30s.
 
I have noticed that some manufacturers mention using 5W-30 under certain circumstances instead of 5W-20. Does Honda mention this in your manual? The only Honda I own recommends 10W-30, but 5W-40 may be used for better cold starting.
 
Motor oil of 0W20 grade is supposed to be kind of like 5W20, but with better cold start performance in winter in colder climates. Once engine is warm, they should both flow like 20 grade oil. So we're effectively down to 5W20 vs 5W30 discussion, of which there are already plenty in the archives.

Car manufacturers know their cars, so I would trust Honda on making a sound motor oil recommendation. Besides the grades, I suppose that Honda may also have a list of additional requirements that the oil should satisfy. I don't see a problem with using 0W20 oil as long as the oil meets all of Honda's requirements. I would not run a different grade unless there was a good reason for that. Sometimes it is hard to find 0W20 oils in the usual retail establishments. For this reason, in a place with warm winters, I'd consider running 5W20 grade of acceptable quality. However, the 0W winter spec is spot on for any place with cold winters.
 
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Originally Posted By: INDYMAC
The only Honda I own recommends 10W-30, but 5W-40 may be used for better cold starting.



That seems like an odd recommendation.. 5W-40 may flow a bit better than 10W-30 in freezing temperatures, but at 40C their kinematic viscosity is close. In fact, I bet a lot of 5W-40 are thicker than most 10W-30 at 40C or hotter. What's strange is that 5W40 is recommended instead of 5W30 or 0W30. This must be some kind of an old car and manual.
 
I don't see any problem with it, especially during a CO Summer. I recently did a similar thing with my 2.4L Toyota engine.
 
Originally Posted By: Zako2
Originally Posted By: INDYMAC
The only Honda I own recommends 10W-30, but 5W-40 may be used for better cold starting.



That seems like an odd recommendation.. 5W-40 may flow a bit better than 10W-30 in freezing temperatures, but at 40C their kinematic viscosity is close. In fact, I bet a lot of 5W-40 are thicker than most 10W-30 at 40C or hotter. What's strange is that 5W40 is recommended instead of 5W30 or 0W30. This must be some kind of an old car and manual.


I don't think of it as old, but old is a relative thing for most people. It's a 2004 S2000. Anyways, it's what Honda recommended through the '09 MY when it was discontinued. There are many opinions on oil viscosity recommendations...most are debatable.
 
Wonder where this will go?
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Your engine will be fine with 0-20 if it is spec'd for it.
 
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The debate about 20s, a decade on is like the debate about hybrids.

Some people didn't get the results that they wanted when they were early adopters (albeit they didn't chose xw-20, it was chosen for them for political reasons), but as per recent posts, they are making bearings with more surface area, and closer clearances, which adapts for lower viscosity, while increasing friction.

Bearing changes as a result of lower viscosity oils, rather than leading says that the OEMs aren't entirely happy with durability and low visc.
 
I have yet to see any significant clearance number changes in modern engines as compared to "older" designs. Running 20wts is nothing new, and is possible in all climates due to the total package design (modern engine management, multi stage fans, superior materials, etc) of modern vehicles compared to previous generations. The supior oils of our day are also taken into consideration.
 
While under warranty follow the OM, after that do as you please. I'd stick with the spec'd oil after the warranty too. I'm still waiting on the hard core evidence [I still haven't seen it though], that a 30 grade oil protects better than a 20 grade oil in applications specifically calling for 20 grade oil. JMO
 
0W-20's are at or near the top of the oil food chain. It's the future, get used to it. 0W-15/-10/-05 have already been developed.

I can't wait the five years from now when someone will post, "Is it okay to use 0W-20 in an engine specd for 0W-10?"
 
Well don't void your warranty by choosing a "wrong" oil weight.

Since I have a part in my owners manual stating something to the effect that for hot or long highway drives "a higher viscosity [than 0W20] may be better" so I usually use 5W-30. I do drive long and hard.
 
To be a little more help in answering your question. Use any one of the following oils (thank CATERHAM and his tireless research on 0W-20's), change it out when your MM says to, and your engine will outlive your interest in the car:

-Sustina 0W-20
-Toyota
-OEM Mazda, Mitsubishi, Cdn Honda/Acura and Subaru 0W-20s made by Idemitsu (SM, GF-4 only)
-ENEOS
-RP
- American Honda 0W-20 made by COP (full syn)
- American Honda 0W-20 " " (syn' blend)
-PP/QSUD 0W-20
-Texas Tea 0W-20
-Mobil Special 0W-20
-M1 AFE 0W-20
-Valvoline 0W-20
-Subaru 0W-20 (SN, GF-5)
-Beck/Arnley 0W-20 (SN, GF-5)
-Castrol 0W-20 (SN, GF-5)
-Other 0W-20s
 
Chris, I see you've participated in this thread: http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2614758#Post2614758.

Let's go back a square or two.

Approximately eight or nine years ago reports of camshaft galling in k-series engines began to show up on various Honda boards (see, e.g., ephatch.com; Honda-tech.com; vtec.net, etc.). (You also can Google "Honda camshaft galling" and find similar reports.) It was never resolved whether the cause of the problem was metallurgical, poor maintenance, abuse, high mileage or a combination of those factors and others. It wasn't a cronic problem, but there was enough concern that people took it seriously. Out of this was borne the advice/recommendations to run the same weight oil that Honda recommended (and still recommends) for its higher performance engines, 5W-30. With time, the problem seemed to abate. Whether this was a result of Honda's efforts or the use of 5W-30 oil is still hotly debated.

In your case, however, your owner's manual "recommends" 0W-20 weight oil. (I put the quotes around the word "recommends" because, if you read the language in the manual, Honda's recommendation is really a mandate.) Honda (and other manufacturers) specify that weight oil in order to comply with CAFE and, thus, receive federal SULEV & ULEV energy credits.

So, if you are concerned about potential engine warranty issues -- as discussed in the thread linked -- 0W-20 weight synthetic motor oil is your only real choice. If, on the other hand, you believe what Trav has recommended in the past (and I'm not trying to put words in his mouth), there is no mechanical reason why you can't run a 5W-30 weight synthetic oil in your V-6 Accord as others are now doing and many more k-series owners have done in the past.
 
Originally Posted By: Chris B.
What are your thoughts on using a quality synthetic 5w30 in a car like a new V6 Honda Accord that calls for 0w20? Wondering if the engine would be better protected with the 5w30. Thanks for any input!

Like others have already said, I would suggest that you stick with the manufacturer-specified weight unless you have a reason to use something else.

With that said, I'm currently running 5W-30 in our Saturn VUE which has a 3.5-liter V6 manufactured by Honda and specs 5W-20. I'm doing this because I have a large stash of FAR G-OIL and UOAs have shown the G-OIL shears down anyway. I have noticed no difference in the way the vehicle feels or performs.
 
Im running a higher viscosity 5w20 "unapproved" oil vs the factory 0w20 (or 10?!)and the engine is quieter and has more full throttle power and smoothness. I want quiet and smooth at the upper RPM torque peak and I traded about 1mpg for it(35 vs. 36mpg average). If you dont mind the clatter and knocking some engines have with a thin 20 then go for it. I have a stick, and cranks tend to walk around more with a stick and I feel they need a bit more vis and zdp than a slushbox. the proof is in my pudding.
 
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