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Oil - Petrol Engine - 0w30 or 5w30

s-preston87

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Hi everyone,

Before i get started i just wanted to apologise in advance... I know there are countless engine oil threads on here but after reading many of these I was unable to find an answer to my question.

I currently own a 2005 accord sport petrol (2.0L) that has done around 128,000 miles.

1) Can 0w30 oil be used in my petrol engine bearing in mind the highish mileage? eg Castrol Edge A5/B5
2) If using 0w30 would I expect to top up every few thousand miles as it being a thinner oil when cold?
3) When the oil is at temperature will the viscosity of the oil be the same as that of a 5w30 oil?

I have been highly highly highly advised NOT to use 0w30 as its a "high mileage petrol engine" and that it may blow my engine due to lack of lubrication. Several mechanics have attempted to explain when the oil is at temp the 0w30 is actually thinner than 5w30 which doesn't make any sense as I thought the only difference is the cold start viscosity (Maybe I am completely misunderstanding)

I've spent a couple of months reading into this and I have hit a brick wall. Any advise would be greatly appreciated. Thanks
 
I agree with you, the running temps should be the same just lower viscosity on start up which is better at cold temperatures.
I think high mileage oils are a bit thicker like me:rolleyes:
 
Honda recommend 0W20. The thinner the oil is is on cold startup the better, because that's when most engine wear happens. If you try it you won't go back to a 30 oil I promise you.
 
I have been highly highly highly advised NOT to use 0w30 as its a "high mileage petrol engine" and that it may blow my engine due to lack of lubrication. Several mechanics have attempted to explain when the oil is at temp the 0w30 is actually thinner than 5w30 which doesn't make any sense as I thought the only difference is the cold start viscosity (Maybe I am completely misunderstanding)


They are talking rubbish !!! A 0W30 and a 5W30 will both have a viscosity in the same range at 100°C and can be considered to be the same. The 0W will have a 'relatively' lower viscosity, and hence thinner, at cold startup which means it will pump around the engine quicker and provide faster lubrication during the critical startup phase.

0W30 A5/B5 will be fine for your engine.
 
They are talking rubbish !!! A 0W30 and a 5W30 will both have a viscosity in the same range at 100°C and can be considered to be the same. The 0W will have a 'relatively' lower viscosity, and hence thinner, at cold startup which means it will pump around the engine quicker and provide faster lubrication during the critical startup phase.

0W30 A5/B5 will be fine for your engine.
That's really good to hear. Cheers
 
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Thank you peeps for the info. It confirmed everything I was thinking in the first place. I think i need to keep well clear of these so called mechanics.

Any one using the lower viscosity oil seen their oil consumption increase?
When I usually use 5w30 i rarely have to top up but I'm ***uming the thinner the oil the more chance of the oil "burning off" so regular tops are required? Or possible oil leak?!?!
 
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So I've ordered 4ltrs +1 of Castrol Edge A5/B5 0w30 and a genuine oil filter. Hopefully should complete it this weekend.
I'll be interested to see how better she runs as it looks to be a no brainer. Hopefully fuel economy should increase as well
 
I've just gone the other way on my 2.4 petrol and changed from 5w30 to 5w40. Would 0w30 be better for the next change?
 
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I've just gone the other way on my 2.4 petrol and changed from 5w30 to 5w40. Would 0w30 be better for the next change?
I went 5w/40 in the summer and although i was happy at first (engine appeared a little quieter cold) now the colder weather is here it is not as quiet on start up! Having read up on old posts here i have just bought some Exol 0w/30 fully synthetic A5B5 and intend to change it this week.
Given most wear occurs on start up the 5W40 is just too thick in winter so id replace it asap.Not sure what i was thinking lol but i will never go higher than 30 again.I may even try the 0W20 at some point but ****yzing everyones input here over the years the 0W30 seems the safe option.
 
I went 5w/40 in the summer and although i was happy at first (engine appeared a little quieter cold) now the colder weather is here it is not as quiet on start up! Having read up on old posts here i have just bought some Exol 0w/30 fully synthetic A5B5 and intend to change it this week.
Given most wear occurs on start up the 5W40 is just too thick in winter so id replace it asap.Not sure what i was thinking lol but i will never go higher than 30 again.I may even try the 0W20 at some point but ****yzing everyones input here over the years the 0W30 seems the safe option.


Trust Honda. They will have done lots of testing in lots of climates to come to conclusion that 0W30 is best !
 
Correct! My own logic was as the engine was getting older if not a high miler,a slighly thicker oil would be better.In hindsight it was a stupid move with this engine as it has the potential to decrease supply/flow of oil especially at start up to the top end of engine.Ok we maybe splitting hairs 5w40 might never be a problem but as you say 0W/30 specified for a reason.
I wonder if those owners whose petrol accords have been around the clock two maybe three times stuck to recommended fluids?
 
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Apart from the price. What is the difference between - Castrol Edge 0W-30 C3 and Castrol Edge 0W-30 A5B5 ?
 
A5/B5 is for cars without a DPF and C3 is low SAPS oil which are for DPF equipped vehicles.

Thanks for that info
. Does that mean both are ok for petrol engine, Would one be better than the other in a petrol engine ?
 
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