As a member of bobistheoilguy.com for 3 years, I've seen many oil analysis reports. I recently drained the factory oil out at about 5k miles. Went to M1 EP then to GC. After running German Castrol 0w-30, which IMO is the best xw-30 on the market, it was much too thick for my Accord (2.4L).

Car was extremely sluggish for 1k miles and at that point i couldn't take it anymore so I put in M1 0w-20. What a difference. Much better power and better gas mileage. I can't believe the difference is that great going from a 12.2 centistoke oil to a 8.6 cSt oil. The difference from factory fill 5w-20 to M1 EP 10w-30 wasn't that bad, as M1 is on the thin side for a 30wt oil @ 10.5 cSt @100C. After seeing so many great 20wt oil analysis reports, I'm no longer skeptical of their wear protection. In fact, many 20wt oils are putting up better numbers then the 30wt oils.

We will be sticking with M1 5-30 :)

I just run hypoid oil in mine. Gas mileage is 1-2 MPG higher, but talk about PROTECTION for those cylinders!

It really doesn't matter what oil you run. Various parts of the world run different grades/brands for the same exact engines sold in the US. However, if oil analysis suggests a 20wt is providing as good or better wear protection as anything higher, it makes no sense to use anything but a 20wt. Shell did a study and found that the oil film thickness at the ring area was thicker with a 5w-20 than a 15w-40. More HP and MPG also. ;) Hypoid oil? Is that Scamsoil? ;)

We will be sticking with M1 5-30 :)
Same here.
5w-30 is what the Honda V6 first specified and I've seen no info that the engine changed when Honda switched to 5w-20. This change was for Honda's benefit, not yours or mine.

The change was for Honda's CAFE rating. (corp average fuel efficiency). However, the last 4 years of data has trickled in and 5w-20's have outperformed their 30wt cousins in many cases. I'm not suggesting switching to a 5w-20 if your running a 30wt or your car calls for a 30wt. I'm simply saying that Honda and Ford have tested 20wt oils in their engines and they are rock solid. Nothing to fear with the low viscosity oils that I've seen.

Hypoid oil? Is that Scamsoil? ;)No, it is a type of oil, in this case, 80w-90 synthetic. Same as outboard lower casings use.

But based on what you are telling us, thinner is better, so since my grandma's Singer has been going strong since 1935, I think I will drain the thick synthetic and switch to sewing machine oil. I'll bet my mileage goes WAY up!

I did not say thinner is better for ALL applications. Let me restate what I am saying. It doesn't matter what viscosity you run. In Austrialia and Japan, Honda's run on anything from a 10w-30 to a 5w-50. In the US, it's driven by CAFE/EPA fuel ratings. Those that fear running 20wt oils shouldn't have any based on the data. Therefore, you get the best of both worlds with these new 20wt oils. Better HP/MPG and great wear protection. ;) Start up wear is also diminished when using a thinner lubricant.

Page 22 of the following article. Film is thicker in the ring area with a lower viscosity oil

http://www.iantaylor.org.uk/papers/IMechEFE2000.pdf

You can't really say much about oil, I don't care what analysis was performed. In the end, if you change it regularly and soon, you and me are on the same boat. Honda oil ratings are full of crud. From 98-00 all Accords were spec'd 5W-30. Then from 01+ they spec'd 5W-20. Then later they backtracked and said all Accords back to 98 now should use 5W-20.

In the Odyssey, they previously used 5W-20. For no reason, they switched to 0W-20. Ohhh wait, that was the year when the Odyssey officially became an ULEV....ahhh now I'm getting the picture...

Dealers dump in the cheapest piece of crap oil ever made in any grade they can get their hands on. Just look at your maintenance records, I bet at least a few of your Accords got 5W-30 bulk in them. And they're still under warranty are they not? And they are still running?

So?? Isn't arguing about this kinda pointless? My car runs smoother on 10W-40. Yes, I use 10W-40. Sue me. :thumbsup:

i run 5w-30 in mine, and still no signs of burning oil.... even after 250k+ miles......... :biggrin: :jumping:

Start up wear is also diminished when using a thinner lubricant.

Page 22 of the following article. Film is thicker in the ring area with a lower viscosity oil

http://www.iantaylor.org.uk/papers/IMechEFE2000.pdfApples & oranges. The thicker oil they mention (less than 1 micron thicker, btw) at the upper piston ring area is due possibly to the thinner oil passing between the ring gaps more readily. Makes sense, and only refers to when the engine is running.

But this has nothing to do with start-up wear. Many other factors come into play here, such as time between starts. Regardless of that oil film thickness while running, over time the oil is going to thin out as it sits static. Eventually, you will have almost no oil during start-ups.

I was only messing with you on the hypoid/sewing machine thing. But this argument is much older than you and & put together; and while good info is always appreciated, not much you can say to convince most people. Change it often, and it doesn't matter what you run (see the news where the guy is using filtered deep-fat fryer oil in his diesel?). Change it later (I prefer a 10-15k interval), and you better have some good oil in it.

And regardless what tests show about 20w oils, if you run a mono-weight oil, 30w will have more lubrication properties than a 20w over time. It's simple physics; if the oil starts out thicker, it will be thicker longer. Its the additives that make the difference, especially early on.

I actually agree with you. If your running extended drains, definitely use a Group IV/V based oil. Again, my point was that you don't have to fear using the 5w-20 oils. They have been extensively tested by the engineers who design these engines. On www.bobistheoilguy.com, you'll find that most believe thicker is not better most of the time. However, some engines like the LS1 do prefer a thicker oil then what is spec'd for it. This is based on used oil analysis. Regarding the 10w-40, that is another point I was trying to make. You'd find in Europe/Austrailia this is what they use often. I'd rather stick with a 5w-20 and gain HP/MPG while keeping the protection. To each their own. ;)

i run 5w-30 in mine, and still no signs of burning oil.... even after 250k+ miles......... :biggrin: :jumping:

Now that's the kind of backing I want... pure mileage records...

What brand do you use?? Did you use that brand consistently?

Their are several people on bobistheoilguy.com that have over 150k miles using nothing but Motorcraft 5w-20. This one guy in particular tows a boat as well. Any oil will get the job done. With conventional, just don't take it too far.

Now that's the kind of backing I want... pure mileage records...

What brand do you use?? Did you use that brand consistently?

215k miles on '91 Corolla wagon
10w-30 Castrol GTX (dino) every 3500 miles.
Fram oil filter (except past 4 years)
No smoke, no oil consumption. Runs great.
Engine is very clean.
No engine work excpet timing belt changed every 60k miles.
Towed small boat on vacation 1500 miles a few years.
Foot stays in the floor.
Keeps going, and going . . .

Thought about changing to M1 just to extend the drain interval, but my 17 year old daughter got her license and wants to do the oil change. :D

No, it is a type of oil, in this case, 80w-90 synthetic. Same as outboard lower casings use.

you're joking I hope. right?

5w-20 vs. 5w-30. not THAT much different no matter what any annalysis to the .001% of this and that says. if 5w-20 was bad, honda wouldn't recommend it. stick with what they reccomend and you can't end up with the "warranty" arguements of, "well, you didn't use the right oil, etc". I know they can't really hold that against you, but it's an arguement to avoid if it's as easy as oil weight. 5w-20 mobil 1 for me. :thmsup:

you're joking I hope. right?Right... http://www.driveaccord.net/forums/showpost.php?p=41353&postcount=11

Right... http://www.driveaccord.net/forums/showpost.php?p=41353&postcount=11
sorry, admittedly didn't read all of it. just saw the 80/90 thing and wondered if someone would really do that. :lmao:

buster,

What did you do with the GC? I plan on running GC next in my '02 V6 for a couple of 7-10k mile intervals. We'll see how it does in the V6.

And regardless what tests show about 20w oils, if you run a mono-weight oil, 30w will have more lubrication properties than a 20w over time. It's simple physics; if the oil starts out thicker, it will be thicker longer. Its the additives that make the difference, especially early on.
Additives make a difference later on, as well . . . they contribute to sludge. This is why 10w-40 dino oil fell out of favor. It has a high additive content (viscosity modifiers) in order to cover the wide viscosity range. Generally, the narrower the viscosity range, the better, in this respect. However, it should be noted that synthetics can be formulated to handle a wider viscosity range without the additives that deteriorate in dino oil.

Additives make a difference later on, as well . . . they contribute to sludge. This is why 10w-40 dino oil fell out of favor. It has a high additive content (viscosity modifiers) in order to cover the wide viscosity range. Generally, the narrower the viscosity range, the better, in this respect. However, it should be noted that synthetics can be formulated to handle a wider viscosity range without the additives that deteriorate in dino oil.

I wouldn't consider viscosity modifiers additives. VII (viscosity index improvers) are more to do with the base stock package than the additive package.

I drained the GC out with only 1k on the oil. It was making the car extremely sluggish. GC will normally make cars run better, but some cars, it's just too thick. The 2.4L runs best on a 20wt or light 30wt from my experience. AS time goes on and the engine wears in a bit, I'll eventually move up a grade but as long as oil analysis and oil consumption is in check, I'll stick with a 20wt. Thin and thick is a hot topic right now.

Some Qs (sorry to bring so many posts back from the dead, but I'd rather do that than start new oil threads):

I'm currently running M1 0W40 in my I4, because I had it on hand from my previous car, which was totaled. How bad is this at startup? I'm currently in South Florida, but I might take a couple of trips up to NYC during this winter. Money is not an issue, but I'd rather not waste it if it's not hurting me. I plan to change it out @ 5k miles regardless.

I can't seem to find 0W20 anywhere, I assume the stock has been depleted. Is M1 5W20 on a 6k miles OR 6 mo. OCI pretty bulletproof in this engine? I'm not really interested in EP/long wear oils since they are not available in the proper weight.

P.S. I just averaged 33 MPG over 441 miles with the 0W40, 30% city & AC on 50% of the time, driving normally, cruising at 75-85 MPH on the highway, stock 15" tires kinda worn but properly inflated. Good/bad?

Everything you said sounds about right to me. I run a 10W-40 in my engine and the engine loved it...ran real smooth and quiet. Just dumped in some Pennzoil High Mileage 10W-30 and the engine hates it...runs rough, loud, less power, etc. But no smoke...

Now that's the kind of backing I want... pure mileage records...

What brand do you use?? Did you use that brand consistently?

castrol 5w30

BTW, I just sold all my GC -- I had stocked 16 quarts (8 green, 8 amber) for the 1.8T, now that she's gone I had to get rid of it. So I won't be using 0W30.

0W40 is great at startup. It might be a little "thick" at operating temperature for your new car though. The 0W30 would do better than the 0W40 IMHO.
This engine is pretty bulletproof with almost any weight oil with appropriate changes.
You should be able to find the correct weight in long drain oils.
Oh yeah, I would prefer for you to revive old threads instead of creating new ones. :thmsup:

Oh yeah, I would prefer for you to revive old threads instead of creating new ones. :thmsup:

AMEN

Keeps all the good info in one place so I don't have to go searching left and right for it when newbies come and ask questions. It's not their fault, our forum is pretty hard to search...unless you've been around the block a few times and remember a specific thread from a couple years ago