GN4 10W-30 or 10W-40

[stephen]

I stopped by my dealer last week and requested the oil and filter for a 2014 Forza. At first, he didn't know what a Forza was, so he looked it up on his computer terminal at said "oh, that's NSS300", but I still don't think he knew what one was. Anyway, he came back with an oil filter and 2 quarts of 10W40 GN4 Pro Honda oil.

It's now Sunday morning and I read the instructions for my oil change and the manual recommends 10W-30, but he sold me 10W-40.

Question: Should I go ahead and use the 10W-40 or go back on Tuesday (the are closed today and Monday) to return the oil and get the 10W-30 that is specified in the manual?

I'm feeling frustrated that I did not take the manual with me or write down what it specified, since I thought that the parts department at a Honda dealer would know what is recommended. Perhaps my frustration is misplaced.

[homie]

Like heath care we have to research and study our own needs and then place an order for exactly what we need and what we don't want. Time and time again I have had faith only to be disappointed my fellow man. Fellowship screams at me from the good book and I still have no trust.

[Alibally]

If you live in hot country then 10w-40 is fine, otherwise better with the 10w-30 as its a little thinner. It'll probably be fine if your stuck.

If you can put your location on your profile if you want that helps with the answers, and Whitenoise won't get all OCD. (You know we all love you Whitenoise)

[stephen]

I just updated my profile. I live in Kansas City. I am unlikely to ride in temps below 50 degrees, but often when it is over 90.

[stephen]

Here is what I found on the Pro Honda Oil website. Since I am not in a hurry, I think that I'll exchange it for the 10W-30.

[fish]

Yes, owner's manual and service manual agrees with you....even though my dealer said either oil is OK..and sold me the 10/40..I'm going with the manuals and purchased the 10/30M and put it in and will use for all future changes.
FISH

[Alibally]

10w-40 is more readily available so if that's in stock that's the one they will sell you.

[stephen]

I went to the dealer to exchange the oil and the same parts guy told me 10W-40 is what the shop "always uses on their oil changes". I simply stated that I wanted to follow the owners manual and use what was recommended. He said 10W-30 was in the manual because of some "California emission requirements", but it was my bike and that I could use whatever. I would normally make a snarky reply, but I just smiled and took my 10W-30 and enjoyed the rest of my day.

[Ninja.turtle007]

Hi,

I have loads of Quantum Platinum 5w 40. Would this be okay to use in the UK?

TIA

Tom

[gn2]

So long as its the wet and slippery type of oil it'll probably be fine.
But 10w30 is what you should be using.

[Jge64]

30 in normal climates
40 in tropical/ temperate climates

Per the manual....

But yeah, anything in the above 5 and below 40 is fine if you change regularly. Don't overthink it.

[iceman]

You start to get into the too thin or too thick territory if you go to the extremes in normal climates - 10w30 covers most countries that go down to -10 below and in the mid 30's in summer (should we have any summer in the UK this year).

[MikeP]

Here is what I found on the Pro Honda Oil website. Since I am not in a hurry, I think that I'll exchange it for the 10W-30.

Thanks for pointing this out. I missed the manual specs on this one.
Nearly 20K while using GN4. Now going to the specified one, but in 10w40 because it is so hot here in the summer.

[SteveP]

The owners manual and service manual recommend Pro Honda oil HP4M. The "M" stands for molybdenum (moly) which is an additive that increases the "slipperiness" of the oil...good for reducing cam and lifter wear and other engine parts. It's not recommended for motorcycles with wet clutches, but we don't have that concern with the Forza.

[iceman]

Most modern oils esp. fully synth have added stuff to make the oil better at lubrication for longer - you do not need special Honda oil. Honda sometimes uses Moly other manufacturers use all kinds of things that do the very same thing. If your in the UK, Castrol fully synth Power 1 Racing 4T gets Honda's and Suzuki's recommendation - over the top for the PCX but still a top-notch fully synth 4T long lasting oil (10w30 or 10w40) and a nice price too (4L's for £31 delivered off Amazon).

[you you]

Is GN4 GN2s older brother?