Oil - 0W30 or 5W30?

[Thrash]

Hey guys,

My car (Mini Cooper) is 'supposed' to take 0W-30 oil, the handbook highly recommends Castrol Edge of course which is priced pretty highly. I was low on oil one day and popped into a local supermarket, they only stocked 5W-30. At the time my view was that any oil is better than no oil, so I bought the 5W-30 topped up and away I went. Since then ive topped up with 5W-30 again due to the price, it seems to be drinking oil pretty quickly though and ive put in about a gallon in the past few months which seems quite a lot.

Im just curious if using 5W-30 is making economical sense, is it damaging the car and being consumed faster? Would I better just getting the 0W-30 as recommended?

Thanks in advance

[Schermerhorn]

0w30 is thinner than 5w30 so your car would probably consume it much quicker if you put that in.

Flush the engine oil and put the correct oil in and see how you get on.

[BritishRacinGrin]

Thrash said:

Im just curious if using 5W-30 is making economical sense, is it damaging the car and being consumed faster? Would I better just getting the 0W-30 as recommended?

Of course it's not making economical sense, your saving a couple of notes at the potential cost of a two grand engine bill!
A cost compromise on oil is NEVER a good compromise. The correct oil specified for the engine is ALWAYS worth it.
That said, the engine cannot read the label on the bottle so if you want you can ignore the castrol edge recommendation and look for BMW/Mini's oil standard code, for my BMW it was 5w40 with LL-02 standard... buy any oil which meets that standard and you're away. I'm putting Petronas oil in mine, fully synthetic and about five quid a litre from Euro Car Parts / Car Parts 4 Less.

[Chongwong]

Try looking on eurocarparts or other online retailers and see how much the correct type of oil is, it may even end up cheaper than the supermarket stuff.

I got 5 litres for about £13 quid for my car.

[GavinPearson]

The reason for using zero weight oil is purely fuel economy in the British climate. If you are sending a car to the Arctic circle, you use zero weight out of necessity to keep the oil pumping when it is seriously cold, but this isn't the case here.

Provided the oil has the right additive spec in it, it should be fine.

[powerstroke]

GavinPearson said:

The reason for using zero weight oil is purely fuel economy in the British climate. If you are sending a car to the Arctic circle, you use zero weight out of necessity to keep the oil pumping when it is seriously cold, but this isn't the case here.

Provided the oil has the right additive spec in it, it should be fine.

This !! 0\30 might be slightly more fuel efficient for short journeys the 5\30 may give better engine protection and lower oil consumption ...

[HertsBiker]

How many miles on the car, and what sort of journeys do you do?

[Steve H]

Thrash said:

ive put in about a gallon in the past few months which seems quite a lot.

It is

[DanielJames]

Steve H said:

Thrash said:

ive put in about a gallon in the past few months which seems quite a lot.

It is

Even my ITR has used less

[IanCress]

Our 52 plate Cooper uses a lot of oil, although a gallon in a couple of months is excessive to say the least! Are you sure you don't mean a litre?

[kambites]

How many miles have you done in those couple of months? If the answer is less than about 5000, there's something very wrong with your engine.

[boz1]

Thrash said:

.... ive put in about a gallon in the past few months which seems quite a lot...

Seriously?! You realise a gallon is 4.5 litres? That would probably be close to the total oil capacity of your engine. Are you sure you don't mean a litre?

[xxChrisxx]

BritishRacinGrin said:

Of course it's not making economical sense, your saving a couple of notes at the potential cost of a two grand engine bill!
A cost compromise on oil is NEVER a good compromise. The correct oil specified for the engine is ALWAYS worth it.

If you are talking about substituting Castrol for vegetable oil then I agree. If you are talking 5w30 for 0w30, then it's absolutely fine. Both 0w30 and 5w30 edge are both LL-04 oils. It's cheaper, and it doesn't get burnt as quickly.

Super piss thin oils are put in for one reason, and one reason only. CO2. If a manufacturer is close to the line on a tax band, the reduction cold start losses from a lighter weight oil can save the 1 or 2 g/km to get them over the line.

If you were in the arctic circle, you may need the thinner oil. Even though the UK gets stty weather, it's generally a mild climate. So you have leeway with cold oil thickness.

[kambites]

Surely the cold viscosity isn't going to effect the official CO2 figures? That test is run entirely hot, isn't it?

[xxChrisxx]

kambites said:

Surely the cold viscosity isn't going to effect the official CO2 figures? That test is run entirely hot, isn't it?

Engine temp should be at 22±2°C if memory serves.

There is both a cold start and how start test. It's why there is a big push is cold start gizmos to get the engine up to temperature quickly. Oil takes a good deal longer to warm up, hence a low cold viscosity.

Edited by xxChrisxx on Monday 10th November 11:40