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0W-30 or 5W-30

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Lost count of the number of times people have asked am I okay using a 5W-30 oil instead of the recommended 0W-30?

Well watch this video and note the difference, when cold, between the 0W and the 5W and imagine the difference this makes in how fast the oil gets to the vital components in the engine when you start it up.

When these two oil are warm then they will flow identically.

One of the main reason people want to use a 5W is because they are generally cheaper because it is harder & more expensive to create a 0W and so the prices are higher.

Hope this helps.

https://youtu.be/V5a4kP-5Jiw
 
@ Graham

Not exactly telling the whole story is it?

According to the comments that video was posted by The Siberian Society of Automotive Engineering so we can make an educated guess at the temperature that test was taken at.

5W is supposed to operate at -25 deg C whereas 0W is designed to operate well below that as stated in my Accord Tourer manual.
 
Correct but even at room temperature there will be a noticeable difference between the flow of a 0W verses a 5W.

I would prefer my oil to get around the engine as soon as possible at startup!
 
This shows operating temperatures of an oil range or viscosity, temperatures have to be very low to impact parameters:

3PJ4M7T.png



I'm an advocate of using the specified oil and will probably go back to 0w30 in the winter, but it is very runny, whose to say that isn't a problem, if it runs off all the components quickly after shutdown leaving them unprotected on start up.
 
Yes the graph looks misleading so found this to help explain:

In a 10w-40 for example the 10w bit (W = winter, not weight or watt or anything else for that matter) simply means that the oil must have a certain maximum viscosity/flow at low temperature. The lower the "W" number the better the oil's cold temperature/cold start performance.
The 40 in a 10w-40 simply means that the oil must fall within certain viscosity limits at 100°C. This is a fixed limit and all oils that end in 40 must achieve these limits. Once again the lower the number, the thinner the oil: a 30 oil is thinner than a 40 oil at 100°C etc.

Cold cranking viscosity limits, determined by the CCS, are defined in the SAE J300 Standard, as shown below:

Cold Crank Viscosity, Low temperature viscosity (mPa∙s) Max (CCS), 0W 6200 @ -35, 5W 6600 @ -30, 10W 7000 @ -25, 15W 7000 @ -20, 20W 9500 @ -15, 25W 13000 @ -10
 
I phoned Honda uk a couple of weeks ago regarding what grade oil to use in my 06 Accord i-cdti they said 5w30 , i also rang a local Honda dealer they also said they use 5w30 as this grade is more suitable for older higher mileage engines which most now are, can't beat the advice of the manufacturer, problems are more likely to occur from lack of servicing over the vehicles life, key is regular oil and filter changes.
 
You can use either it’s your choice but advice and recommendation is 0w30 from me and many in this community.
 
Ive noticed a lot of divided opinions on this subject , my Honda had one owner from new and a Full stack of service invoices (fsh) every service done at the same supplying Honda dealer upto present mileage 103k and looking through the service receipts half the services were done with 0w30 and half were done with 5w30 (not in any order).Engine is as smooth and quiet as a sewing machine , my car has been running approx 50k on 0w30 and 50k on 5w30 at this stage of the cars life probably won't make much difference if I use 0w30 or 5w30 both grades recommended in the Honda manual and opie and miller oils sites, not going to get hung up about it , its an old car and the damage would of been done before I got it , quietest diesel engine I have owned.
Big question is even though its got a full comprehensive Honda service history should I have walked away from buying the car because 5w30 oil has been used on half the services ?
 
antdad, my thoughts exactly, not trying to upset anyone on here ,this subject seems a bit of a minefield and was just trying to explain what my research had thrown up, opie oils also have a offer on spend over £40 and get £10 off
 
oilman said:
In the UK 5w and 0w perform pretty much the same, so makes little difference. The main reason 0w-30 is recommended is for economy reasons.

Cheers,

Guy
And the reason lots switch to 5W is because it's usually cheaper!

People need to be aware that the viscosity grade is not the most important factor when selecting an oil. Its performance category (i.e. A5/B5) is what defines the oil's quality rather than the grade.
 
Grayedout said:
And the reason lots switch to 5W is because it's usually cheaper!

People need to be aware that the viscosity grade is not the most important factor when selecting an oil. Its performance category (i.e. A5/B5) is what defines the oil's quality rather than the grade.
True, also there is a lot more choice of 5w-30 than there is 0w-30.
 
I am happy to use either 0w30 or 5w30 with the correct performance category, many will have bought cars where all the oil changes and oil used cannot be verified or known in the cars life so damage wear could of occured before the car was bought , a lot of cars have full service history but that means nothing if the owner never checks fluid levels between services which I think nowadays is common, i have bought two cars in the last 18 months both i thought had humming wheel bearings which in fact was tyre tread which had worn irregulary more than likely due to tyre pressures not being checked or tyres under or over inflated for a length of time, as i said previously regular oil and filter changes are key.
 
Both regular oil/filter changes, and never letting the oil level drop below the minimum on the dipstick.

Confirmation of (or any resultant damage) from the latter will not be mentioned on any service schedule, only a check with ear, and look up the sump will give the mechanic in all of us an idea of the quality of previous ownership.
 
Whatever oil you choose to use... just make sure it's a low SAPS one, don't go for semi only fully synthetic and stick to a well know brand and you'll be fine. Personally I use Total 0w30 low saps fully synth as I've been able to get 7lts of that for less than £50 which does a complete oil change and leaves me enough for any top ups it might need. Normally I'm left with 1lt when it's time to do the next oil change (every 7-8k). I've still got an unopened bottle here, so I might just buy 6lt next time.
 
 
Cliffordski said:
Low SAPS is important if your car has a DPF, if not then it doesn't matter.
 

it does if you don't want your EGR valve getting clogged up.
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